Fix #4649: Updates audio option name

[theMr17]

Explanation

Fixes #4649

This PR changes the audio_language & audio_language_activity_title string in strings.xml file to Preferred Audio Language.

Essential Checklist

• The PR title and explanation each start with "Fix #bugnum: " (If this PR fixes part of an issue, prefix the title with "Fix part of #bugnum: ...".)
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[adhiamboperes]

LGTM, thanks @the-mr17!