#1771: fix mvn url updater

[hohwille]

This PR fixes #1771

Implemented changes:

• Fix small issues from PR #1771: Change MvnUrlUpdater to extend GithubUrlReleaseUpdater #1781

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Checklist for this PR

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• When running mvn clean test locally all tests pass and build is successful
• PR title is of the form #«issue-id»: «brief summary» (e.g. #921: fixed setup.bat). If no issue ID exists, title only.
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  with internal

[coveralls]

Pull Request Test Coverage Report for Build 23651656096

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 19 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.01%) to 70.39%

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Files with Coverage Reduction	New Missed Lines	%
com/devonfw/tools/ide/url/tool/mvn/MvnUrlUpdater.java	19	0.0%

Totals
Change from base Build 23641462284:	-0.01%
Covered Lines:	10800
Relevant Lines:	14734

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💛 - Coveralls