bugfix: the vgroup_table in the SQL files of all databases should use a three-column unique constraint.

[maple525866]

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• I have registered the PR changes.

Ⅰ. Describe what this PR did

fixed the vgroup_table tables in the SQL files of databases other than MySQL, and used a three-column unique index to ensure high availability for disaster recovery migration.

Ⅱ. Does this pull request fix one issue?

fixes #7877

Ⅲ. Why don't you add test cases (unit test/integration test)?

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 71.02%. Comparing base (97abcd2) to head (7141c54).
⚠️ Report is 2 commits behind head on 2.x.

Additional details and impacted files

@@            Coverage Diff            @@
##                2.x    #7881   +/-   ##
=========================================
  Coverage     71.02%   71.02%           
  Complexity      797      797           
=========================================
  Files          1300     1300           
  Lines         49601    49601           
  Branches       5871     5871           
=========================================
+ Hits          35228    35230    +2     
+ Misses        11463    11460    -3     
- Partials       2910     2911    +1     

see 5 files with indirect coverage changes

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[funky-eyes]

LGTM