chore: risedev clean java targets

[fuyufjh]

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What's changed and what's your intention?

As title.

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
• All checks passed in ./risedev check (or alias, ./risedev c)
• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

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Release note

If this PR includes changes that directly affect users or other significant modifications relevant to the community, kindly draft a release note to provide a concise summary of these changes. Please prioritize highlighting the impact these changes will have on users.

[codecov]

Codecov Report

Merging #12600 (3fca255) into main (a8f21ed) will decrease coverage by 0.01%.
Report is 20 commits behind head on main.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main   #12600      +/-   ##
==========================================
- Coverage   69.30%   69.30%   -0.01%     
==========================================
  Files        1469     1469              
  Lines      241061   241061              
==========================================
- Hits       167072   167069       -3     
- Misses      73989    73992       +3     

Flag	Coverage Δ
rust	69.30% <ø> (-0.01%)	⬇️

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[xxchan]

nit: the condition for the task is condition = { env_set = ["ENABLE_BUILD_RUST"] }

[xxchan]

Should we add if $ENABLE_BUILD_RW_CONNECTOR or sth?

[fuyufjh]

Refactored