goto-diff: add missing break in output_functions UI switch

[tautschnig]

The XML_UI case of the user-interface switch in goto_difft::output_functions fell through to the next case. Add the missing break so --xml-ui emits only its own "not supported yet" message.

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[Copilot]

Pull request overview

This PR updates goto-diff’s goto_difft::output_functions() UI switch to add an explicit break; in the XML_UI case.

Changes:

• Add break; after emitting the "XML output not supported yet" message in the XML_UI case.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.68%. Comparing base (7483d0d) to head (19f9f84).

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #9084   +/-   ##
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  Coverage    80.68%   80.68%           
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  Files         1714     1714           
  Lines       189593   189593           
  Branches        73       73           
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  Hits        152979   152979           
  Misses       36614    36614           

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