[maven-4.0.x] Fix mvnup to replace deprecated ${basedir} in repository URLs

[gnodet]

Summary

Backport of #12105 to maven-4.0.x.

• Fix CompatibilityFixStrategy.fixRepositoryExpressions() to replace deprecated ${basedir} and ${pom.basedir} with the canonical ${project.basedir} form in repository and pluginRepository URL elements (including inside profiles)
• Previously the method only logged a warning but never performed the replacement
• Add 5 tests covering repositories, pluginRepositories, profiles, and the no-op case

Context

Maven 4 introduced MavenValidator (MNG-8677, PR #2158) which validates that repository URLs are fully interpolated. When a POM uses ${basedir} in a repository URL (e.g. file://${basedir}/internal-repository), this can fail validation since ${basedir} is a deprecated form that may not be interpolated in all contexts (notably during transitive dependency resolution).

The pom. prefix was deprecated in favor of project. (MNG-7244), and prefixless expressions were dropped (MNG-7404).

See: gnodet/maven4-testing#13299

Test plan

• All existing CompatibilityFixStrategyTest tests pass
• New tests verify ${basedir} → ${project.basedir} replacement in repository, pluginRepository, and profile repository URLs
• New test verifies no modification when URLs already use ${project.basedir} or contain no expressions

Claude Code on behalf of Guillaume Nodet

[github-actions]

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