Adjust triggers for Selenium workflow (backport #14017)

[mergify]

Proposed Changes

From #14014, we learned that the indentation was causing workflows to
not trigger. However, this did not seem to affect when the workflow file
itself was changed. In any case, YAML is sensible to indentation,
therefore this change is 'correct'. Removing single quotes from paths
with '*' at the end, because it is not required according to YAML and
GitHub documentation.

The path triggers now match the Selenium workflow that runs on commits
to main and release branches.

Types of Changes

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• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
• Documentation improvements (corrections, new content, etc)
• Cosmetic change (whitespace, formatting, etc)
• Build system and/or CI

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This is an automatic backport of pull request #14017 done by [Mergify](https://mergify.com).