Add flag com.android.providers.media.flags.enable_oem_metadata_update to trunk_staging.

This change was automatically created by advancing the Gantry workflow at:
https://releasetracker.partner.android.com/changes/76uh0ra000001?build_unique_id=android_platform_mediaprovider
Do not edit this file manually or revert this change - use the Gantry workflow to manage the state of this flag.

Bug: 352528913
Flag: com.android.providers.media.flags.enable_oem_metadata_update
Ignore-AOSP-First: AConfig change for future AOSP release
Change-Id: Ic45eaa0a10bc2fb3a4dfaf08fa18705ffcc72814