#2423: isRepositoryUpdateAvailable is not covered by any test that reaches the comparison

[JoelAdbu]

This PR fixes #2423

Implemented changes:

• enhanced ProcessContextGitMock to support sequential Git outputs by adding a per-command FIFO (addCommandOutput), allowing multiple git invocations within a single test flow to return distinct results
• updated testIsRepositoryUpdateAvailableNoUpdates to simulate a configured upstream and identical local/remote commit IDs, ensuring the actual commit comparison is reached
• added testIsRepositoryUpdateAvailableUpdates to cover the case where local and remote commit IDs differ and an update is available
• added additional edge case tests covering missing upstream configuration and null commit IDs
• removed unused test data (errors / outs) and updated the Javadocs to accurately reflect the tested behavior

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Testing instructions

Please add conscise, understandable instructions on how a reviewer can test/verify the functionality of your contribution here:

1. Open GitContextTest
2. Run the newly added tests with coverage.
3. Verify all test pass successfully and verify that GitContextImpl.isRepositoryUpdateAvailable(Path) is covered by the test execution.

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Checklist for this PR

Make sure everything is checked before merging this PR. For further info please also see
our DoD.

• When running mvn clean test locally all tests pass and build is successful
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[coveralls]

Coverage Report for CI Build 34966294534

Coverage increased (+0.1%) to 74.267%

Details

• Coverage increased (+0.1%) from the base build.
• Patch coverage: No coverable lines changed in this PR.
• 4 coverage regressions across 2 files.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

4 previously-covered lines in 2 files lost coverage.

File	Lines Losing Coverage	Coverage
com/devonfw/tools/ide/git/GitContextImpl.java	3	40.82%
com/devonfw/tools/ide/version/VersionSegment.java	1	91.34%

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Coverage Stats

Relevant Lines:	19001
Covered Lines:	14740
Line Coverage:	77.57%
Relevant Branches:	8516
Covered Branches:	5696
Branch Coverage:	66.89%
Branches in Coverage %:	Yes
Coverage Strength:	3.31 hits per line

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💛 - Coveralls

[quando632]

Nice catch on the root cause: the old testIsRepositoryUpdateAvailableNoUpdates built two Lists that never reached the mock, so the commit comparison was never executed. The sequential output queue fixes that, and both the no-update and the update path are now genuinely covered. One non-blocking note inline on the "commit id missing" tests.

[quando632]

Nice now everything looks good for me. You only need to update the branch with main, then we can move this to In-Review :)