fix(lib): templates core path detection

[skjnldsv]

Summary

For some reason, since NC32, the getAppTemplateDirs function returns themes/example/apps/core/templates for core templates, while it used to return themes/example/core/templates.
In any case, seeign the method below, I fully assume this was a mistake initially and that if the app was core, the getCoreTemplateDirs should have been used 🤷

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

AI (if applicable)

• The content of this PR was partly or fully generated using AI

[skjnldsv]

/backport to stable33

[skjnldsv]

/backport to stable32