optimize: add OkHttp and MockWebServer dependencies to resolve version confilcts

[neronsoda]

• I have read the CONTRIBUTING.md guidelines.
• I have registered the PR changes.

Ⅰ. Describe what this PR did

1. Added okhttp version 4.9.3 property declaration
2. Added okhttp and mockwebserver to <dependencyManagement> section in dependencies/pom.xml

Ⅱ. Does this pull request fix one issue?

fixes #7920

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

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[funky-eyes]

Please register your PR in those two files :
https://github.com/apache/incubator-seata/blob/2.x/changes/zh-cn/2.x.md
https://github.com/apache/incubator-seata/blob/2.x/changes/en-us/2.x.md

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 71.61%. Comparing base (1d4e811) to head (2acd4c2).

Additional details and impacted files

@@             Coverage Diff              @@
##                2.x    #7934      +/-   ##
============================================
+ Coverage     71.56%   71.61%   +0.04%     
  Complexity      884      884              
============================================
  Files          1300     1300              
  Lines         49701    49701              
  Branches       5895     5895              
============================================
+ Hits          35569    35591      +22     
+ Misses        11212    11190      -22     
  Partials       2920     2920              

see 10 files with indirect coverage changes

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[neronsoda]

Please register your PR in those two files :
https://github.com/apache/incubator-seata/blob/2.x/changes/zh-cn/2.x.md
https://github.com/apache/incubator-seata/blob/2.x/changes/en-us/2.x.md

I’ll register my PR in both files by today :)