Optimize the Dubbo-config unit tests.

[RainYuY]

What is the purpose of the change?

This PR will do three things:

• Move the IntegrationTest to the dubbo-integration repository.

• Clean up the UT files that are not run during mvn test.

• Remove the module’s dependency on the real Zookeeper.

Checklist

• Make sure there is a GitHub_issue field for the change.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Write necessary unit-test to verify your logic correction. If the new feature or significant change is committed, please remember to add sample in dubbo samples project.
• Make sure gitHub actions can pass. Why the workflow is failing and how to fix it?

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 61.01%. Comparing base (c831fef) to head (ea365b8).
⚠️ Report is 1 commits behind head on 3.3.

Additional details and impacted files

@@             Coverage Diff              @@
##                3.3   #15654      +/-   ##
============================================
- Coverage     61.01%   61.01%   -0.01%     
+ Complexity    11704    11690      -14     
============================================
  Files          1910     1910              
  Lines         86806    86806              
  Branches      13100    13100              
============================================
- Hits          52968    52965       -3     
+ Misses        28419    28417       -2     
- Partials       5419     5424       +5     

Flag	Coverage Δ
integration-tests-java21	33.00% <ø> (-0.01%)	⬇️
integration-tests-java8	33.10% <ø> (-0.02%)	⬇️
samples-tests-java21	32.73% <ø> (+0.03%)	⬆️
samples-tests-java8	30.43% <ø> (+0.01%)	⬆️
unit-tests-java11	59.03% <ø> (+0.02%)	⬆️
unit-tests-java17	58.72% <ø> (-0.01%)	⬇️
unit-tests-java21	58.71% <ø> (-0.01%)	⬇️
unit-tests-java8	59.03% <ø> (+0.02%)	⬆️

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[zrlw]

LGTM