Add more tests for includePanelProcessor.ts

[AgentHagu]

What is the purpose of this pull request?

• Documentation update
• Bug fix
• Feature addition or enhancement
• Code maintenance
• DevOps
• Improve developer experience
• Others, please explain:

Overview of changes:
Adds more tests to includePanelProcessor.test.ts.

Adds assertions to check the errors logged by logger using jest.spyOn

Anything you'd like to highlight/discuss:
These changes are derived from the PR #2639

Testing instructions:

Proposed commit message: (wrap lines at 72 characters)
Add more tests for includePanelProcessor.ts

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Checklist: ☑️

• Updated the documentation for feature additions and enhancements
• Added tests for bug fixes or features
• Linked all related issues
• No unrelated changes

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Reviewer checklist:

Indicate the SEMVER impact of the PR:

• Major (when you make incompatible API changes)
• Minor (when you add functionality in a backward compatible manner)
• Patch (when you make backward compatible bug fixes)

At the end of the review, please label the PR with the appropriate label: r.Major, r.Minor, r.Patch.

Breaking change release note preparation (if applicable):

• To be included in the release note for any feature that is made obsolete/breaking

Give a brief explanation note about:

• what was the old feature that was made obsolete
• any replacement feature (if any), and
• how the author should modify his website to migrate from the old feature to the replacement feature (if possible).

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 61.36%. Comparing base (fe2e1b9) to head (1e2fb8c).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2704      +/-   ##
==========================================
+ Coverage   60.61%   61.36%   +0.75%     
==========================================
  Files         130      130              
  Lines        7170     7170              
  Branches     1480     1515      +35     
==========================================
+ Hits         4346     4400      +54     
+ Misses       2761     2707      -54     
  Partials       63       63              

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[Copilot]

Pull request overview

This PR enhances test coverage for includePanelProcessor.ts by adding comprehensive error scenario tests and logger verification. The changes focus on ensuring both the error output and logger calls are properly tested for various edge cases.

Key changes include:

• Addition of logger spy assertions to existing error handling tests
• Addition of 6 new test cases covering missing files, empty src attributes, URL validation, and cyclic references for both <include> and <popover> elements
• Updates to the expectedErrors array to reflect all error messages that will be logged during test execution

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[gerteck]

LGTM