feat(apigee): add google_apigee_endpoint_attachment

[haarchri]

Description of your changes

add google_apigee_endpoint_attachment

Fixes #564

I have:

• Read and followed Crossplane's contribution process.
• Run make reviewable to ensure this PR is ready for review.
• Added backport release-x.y labels to auto-backport this PR if necessary.

How has this code been tested

via crossplane-playground project in gcp - enabled apigee api first, the deletion of endpointattachment can take up to 2 hours

kubectl get managed
NAME                                                            SYNCED   READY   EXTERNAL-NAME                         AGE
organization.apigee.gcp.upbound.io/apigee-endpoint-attachment   True     True    organizations/crossplane-playground   4h34m

NAME                                                                  SYNCED   READY   EXTERNAL-NAME                AGE
endpointattachment.apigee.gcp.upbound.io/apigee-endpoint-attachment   True     True    apigee-endpoint-attachment   3h2m

NAME                                                                    SYNCED   READY   EXTERNAL-NAME                         AGE
subnetwork.compute.gcp.upbound.io/apigee-endpoint-attachment            True     True    apigee-endpoint-attachment            3h31m
subnetwork.compute.gcp.upbound.io/apigee-endpoint-attachment-internal   True     True    apigee-endpoint-attachment-internal   3h22m

NAME                                                                  SYNCED   READY   EXTERNAL-NAME                AGE
regionhealthcheck.compute.gcp.upbound.io/apigee-endpoint-attachment   True     True    apigee-endpoint-attachment   3h26m

NAME                                                               SYNCED   READY   EXTERNAL-NAME                AGE
forwardingrule.compute.gcp.upbound.io/apigee-endpoint-attachment   True     True    apigee-endpoint-attachment   3h21m

NAME                                                                     SYNCED   READY   EXTERNAL-NAME                AGE
regionbackendservice.compute.gcp.upbound.io/apigee-endpoint-attachment   True     True    apigee-endpoint-attachment   3h25m

NAME                                                                  SYNCED   READY   EXTERNAL-NAME                AGE
serviceattachment.compute.gcp.upbound.io/apigee-endpoint-attachment   True     True    apigee-endpoint-attachment   3h8m

NAME                                                              SYNCED   READY   EXTERNAL-NAME                AGE
globaladdress.compute.gcp.upbound.io/apigee-endpoint-attachment   True     True    apigee-endpoint-attachment   3h31m

NAME                                                        SYNCED   READY   EXTERNAL-NAME                AGE
network.compute.gcp.upbound.io/apigee-endpoint-attachment   True     True    apigee-endpoint-attachment   3h31m

NAME                                                                     SYNCED   READY   EXTERNAL-NAME                                                                                                        AGE
connection.servicenetworking.gcp.upbound.io/apigee-endpoint-attachment   True     True    projects%2Fcrossplane-playground%2Fglobal%2Fnetworks%2Fapigee-endpoint-attachment:servicenetworking.googleapis.com   3h31m

[turkenf]

Thanks for your effort @haarchri 🙌

I didn't see any manual intervention. If you did not trigger uptest just because of timeout, we can add uptest.upbound.io/timeout: "7200" and try. Otherwise, we should add manual intervention.

[turkenf]

After merging previous PR conflict occurred. It might be better to add resources that the same group with one PR.

After resolving conflicts, we can merge, thank you.