[fix](test) Fix BDB JE resource leak in BDBEnvironmentTest causing FE UT timeout

[morningman]

What problem does this PR solve?

The following resource leak issues in BDBEnvironmentTest cause BDB JE checkpoint threads to enter an infinite VLSN consistency retry loop during JVM shutdown, blocking the Maven Surefire process from exiting and triggering TeamCity execution timeout (~3 hours):

1. testReadTxnIsNotMatched: reopens BDB JE master environment and database at the end but never closes them.

2. testRollbackException: has an early 'return' when fe1 is elected as master, which exits the method without closing any of the 3 BDB JE environments.

Fix by wrapping the test logic of both multi-node cluster tests (testRollbackException, testReadTxnIsNotMatched) with try/finally blocks that guarantee all BDB JE environments are closed, regardless of whether the test passes, fails an assertion, or returns early.

Release note

None

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label

[hello-stephen]

Thank you for your contribution to Apache Doris.
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1. What problem was fixed (it's best to include specific error reporting information). How it was fixed.
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3. What features were added. Why was this function added?
4. Which code was refactored and why was this part of the code refactored?
5. Which functions were optimized and what is the difference before and after the optimization?

[morningman]

run feut

[hello-stephen]

FE UT Coverage Report

Increment line coverage `` 🎉
Increment coverage report
Complete coverage report

[hello-stephen]

skip buildall

[github-actions]

PR approved by at least one committer and no changes requested.

[github-actions]

PR approved by anyone and no changes requested.