[ISSUE #12970] Fix NamingMetadataManager.removeInstanceMetadata() error

[MajorHe1]

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What is the purpose of the change

fix #12970

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Verifying this change

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[github-actions]

Thanks for your this PR. 🙏
Please check again for your PR changes whether contains any usage/api/configuration change such as Add new API , Add new configuration, Change default value of configuration.
If so, please add or update documents(markdown type) in docs/next/ for repository nacos-group/nacos-group.github.io

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感谢您提交的PR。 🙏
请再次查看您的PR内容，确认是否包含任何使用方式/API/配置参数的变更，如：新增API、新增配置参数、修改默认配置等操作。
如果是，请确保在提交之前，在仓库nacos-group/nacos-group.github.io中的docs/next/目录下添加或更新文档（markdown格式）。

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 72.27%. Comparing base (0556181) to head (7670ade).
Report is 4 commits behind head on develop.

Additional details and impacted files

@@              Coverage Diff              @@
##             develop   #12971      +/-   ##
=============================================
- Coverage      72.27%   72.27%   -0.01%     
  Complexity      9997     9997              
=============================================
  Files           1309     1309              
  Lines          41991    41991              
  Branches        4405     4405              
=============================================
- Hits           30349    30348       -1     
- Misses          9516     9517       +1     
  Partials        2126     2126              

Files with missing lines	Coverage Δ
...naming/core/v2/metadata/NamingMetadataManager.java	82.27% <100.00%> (+2.53%)	⬆️

... and 3 files with indirect coverage changes

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[wuyfee]

$\color{green}{SUCCESS}$
DETAILS
✅ - docker: success
✅ - deploy (standalone & cluster & standalone_auth): success
✅ - e2e-java-test (standalone & cluster & standalone_auth): success
✅ - e2e-go-test (standalone & cluster): success
✅ - e2e-cpp-test (standalone & cluster): success
✅ - e2e-csharp-test (standalone & cluster): success
✅ - e2e-nodejs-test (standalone & cluster): success
✅ - e2e-python-test (standalone & cluster): success
✅ - clean (standalone & cluster & standalone_auth): success

[wuyfee]

$\color{green}{SUCCESS}$
DETAILS
✅ - docker: success
✅ - deploy (standalone & cluster & standalone_auth): success
✅ - e2e-java-test (standalone & cluster & standalone_auth): success
✅ - e2e-go-test (standalone & cluster): success
✅ - e2e-cpp-test (standalone & cluster): success
✅ - e2e-csharp-test (standalone & cluster): success
✅ - e2e-nodejs-test (standalone & cluster): success
✅ - e2e-python-test (standalone & cluster): success
✅ - clean (standalone & cluster & standalone_auth): success