Adds CustomizeDiff to update computed member_clusters

[gdavison]

Fixes bug where member_clusters did not update the value when either number_cache_clusters or cluster_mode.num_node_groups are changed.

Closes #17161

Release note for CHANGELOG:

resource/aws_elasticache_replication_group: Correctly update computed `member_clusters` values

Output from acceptance testing:

$ make testacc TESTARGS='-run=TestAccAWSElasticacheReplicationGroup_'

--- PASS: TestAccAWSElasticacheReplicationGroup_clusteringAndCacheNodesCausesError (9.85s)
--- PASS: TestAccAWSElasticacheReplicationGroup_useCmkKmsKeyId (631.02s)
--- PASS: TestAccAWSElasticacheReplicationGroup_enableAuthTokenTransitEncryption (744.59s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_Basic (822.91s)
--- PASS: TestAccAWSElasticacheReplicationGroup_enableAtRestEncryption (875.30s)
--- PASS: TestAccAWSElasticacheReplicationGroup_basic (937.70s)
--- PASS: TestAccAWSElasticacheReplicationGroup_Uppercase (942.74s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_NonClusteredParameterGroup (1312.37s)
--- PASS: TestAccAWSElasticacheReplicationGroup_redisClusterInVpc2 (1319.64s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateMaintenanceWindow (1420.75s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateParameterGroup (1736.18s)
--- PASS: TestAccAWSElasticacheReplicationGroup_tags (1142.14s)
--- PASS: TestAccAWSElasticacheReplicationGroup_NumberCacheClusters_Failover_AutoFailoverEnabled (1812.70s)
--- PASS: TestAccAWSElasticacheReplicationGroup_multiAzInVpc (1823.88s)
--- PASS: TestAccAWSElasticacheReplicationGroup_enableSnapshotting (1864.04s)
--- PASS: TestAccAWSElasticacheReplicationGroup_NumberCacheClusters_Failover_AutoFailoverDisabled (2026.85s)
--- PASS: TestAccAWSElasticacheReplicationGroup_vpc (2127.97s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateDescription (2228.73s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_ReplicasPerNodeGroup (2271.59s)
--- PASS: TestAccAWSElasticacheReplicationGroup_FinalSnapshot (1655.61s)
--- PASS: TestAccAWSElasticacheReplicationGroup_NumberCacheClusters_Basic (2993.23s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateNodeSize (3551.78s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_NumNodeGroups (5255.74s)

[YakDriver]

Looks good! 🎉

GovCloud:

(Failure is unrelated and addressed in #17224)

--- FAIL: TestAccAWSElasticacheReplicationGroup_useCmkKmsKeyId (29.41s)
--- PASS: TestAccAWSElasticacheReplicationGroup_basic (1254.29s)
--- PASS: TestAccAWSElasticacheReplicationGroup_clusteringAndCacheNodesCausesError (0.77s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_Basic (1816.40s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_NonClusteredParameterGroup (2148.70s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_NumNodeGroups (4327.18s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_ReplicasPerNodeGroup (2676.22s)
--- PASS: TestAccAWSElasticacheReplicationGroup_enableAtRestEncryption (2167.22s)
--- PASS: TestAccAWSElasticacheReplicationGroup_enableAuthTokenTransitEncryption (2352.83s)
--- PASS: TestAccAWSElasticacheReplicationGroup_enableSnapshotting (1350.37s)
--- PASS: TestAccAWSElasticacheReplicationGroup_FinalSnapshot (1686.92s)
--- PASS: TestAccAWSElasticacheReplicationGroup_multiAzInVpc (1948.51s)
--- PASS: TestAccAWSElasticacheReplicationGroup_NumberCacheClusters_Basic (1845.09s)
--- PASS: TestAccAWSElasticacheReplicationGroup_NumberCacheClusters_Failover_AutoFailoverDisabled (2840.09s)
--- PASS: TestAccAWSElasticacheReplicationGroup_NumberCacheClusters_Failover_AutoFailoverEnabled (2330.90s)
--- PASS: TestAccAWSElasticacheReplicationGroup_redisClusterInVpc2 (809.19s)
--- PASS: TestAccAWSElasticacheReplicationGroup_tags (1903.48s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateDescription (1325.45s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateMaintenanceWindow (1837.21s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateNodeSize (3186.22s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateParameterGroup (991.60s)
--- PASS: TestAccAWSElasticacheReplicationGroup_Uppercase (1232.81s)
--- PASS: TestAccAWSElasticacheReplicationGroup_vpc (2655.56s)

Commercial:

--- PASS: TestAccAWSElasticacheReplicationGroup_basic (890.67s)
--- PASS: TestAccAWSElasticacheReplicationGroup_clusteringAndCacheNodesCausesError (3.25s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_Basic (1583.49s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_NonClusteredParameterGroup (2067.93s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_NumNodeGroups (4870.33s)
--- PASS: TestAccAWSElasticacheReplicationGroup_ClusterMode_ReplicasPerNodeGroup (2434.07s)
--- PASS: TestAccAWSElasticacheReplicationGroup_enableAtRestEncryption (2446.39s)
--- PASS: TestAccAWSElasticacheReplicationGroup_enableAuthTokenTransitEncryption (2601.58s)
--- PASS: TestAccAWSElasticacheReplicationGroup_enableSnapshotting (849.20s)
--- PASS: TestAccAWSElasticacheReplicationGroup_FinalSnapshot (1469.68s)
--- PASS: TestAccAWSElasticacheReplicationGroup_multiAzInVpc (1011.79s)
--- PASS: TestAccAWSElasticacheReplicationGroup_NumberCacheClusters_Basic (3515.87s)
--- PASS: TestAccAWSElasticacheReplicationGroup_NumberCacheClusters_Failover_AutoFailoverDisabled (1869.78s)
--- PASS: TestAccAWSElasticacheReplicationGroup_NumberCacheClusters_Failover_AutoFailoverEnabled (1853.06s)
--- PASS: TestAccAWSElasticacheReplicationGroup_redisClusterInVpc2 (2279.45s)
--- PASS: TestAccAWSElasticacheReplicationGroup_tags (1652.43s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateDescription (2493.84s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateMaintenanceWindow (911.62s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateNodeSize (2004.66s)
--- PASS: TestAccAWSElasticacheReplicationGroup_updateParameterGroup (1301.08s)
--- PASS: TestAccAWSElasticacheReplicationGroup_Uppercase (2341.32s)
--- PASS: TestAccAWSElasticacheReplicationGroup_useCmkKmsKeyId (1123.11s)
--- PASS: TestAccAWSElasticacheReplicationGroup_vpc (1322.74s)

[ghost]

This has been released in version 3.26.0 of the Terraform AWS provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template for triage. Thanks!

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

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