dev/core#4411 fix issue with user language

[jaapjansma]

Overview

This PR does the following in standalone CiviCRM:

• Add possibility to set a user language and if set that language is used for the UI when the user logs in
• Freezes the element for inherit CMS Language under Administer > Localization > Languages, Currencies, Locations

See https://lab.civicrm.org/dev/core/-/issues/4411

@artfulrobot can you review this?

[civibot]

🤖 Thank you for contributing to CiviCRM! ❤️ We will need to test and review this PR. 👷

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[civibot]

The issue associated with the Pull Request can be viewed at https://lab.civicrm.org/dev/core/-/issues/4411

[jaapjansma]

@colemanw thanks for your suggestion I took the suggestion over.
@artfulrobot I fixed the merge conflict and also a style warning.

[colemanw]

@jaapjansma well done