Add test for non-existent file extension pattern (*.qwerty)

[RyanL2004]

Old version:

Test that when using a pattern for a non-existent file extension *.qwerty,
no files are processed despite other valid files being present in the directory.

New version:

Test that when using a pattern for a non-existent file extension *.qwerty,
no files are matched or included in the result, but the directory structure
information is still captured.

This test verifies:

1. The scan completes without errors
2. No files are matched with the non-existent extension
3. Directory structure is still captured but empty since no files match
4. File information is present but content is ignored due to no matches
5. pytest: