fix: Avoid setting PrimaryLanguageOverride when starting Localizationservice

[nickrandolph]

GitHub Issue (If applicable): fixes #1438, fixes: #1543

PR Type

What kind of change does this PR introduce?

• Bugfix

What is the current behavior?

Localization extensions was setting primarylanguageoverride on startup even if culture hasn't been set by user - this was because previously primarylanguageoverride wasn't being persisted by uno

What is the new behavior?

PrimaryLanguageOverride is now only set when culture is changed in Localization

PR Checklist

Please check if your PR fulfills the following requirements:

• [X ] Tested code with current supported SDKs
• [N/A ] Docs have been added/updated which fit documentation template. (for bug fixes / features)
• [ X] Unit Tests and/or UI Tests for the changes have been added (for bug fixes / features) (if applicable)
• [X ] Wasm UI Tests are not showing unexpected any differences. Validate PR Screenshots Compare Test Run results.
• [ X] Contains NO breaking changes
• [X ] Updated the Release Notes
• [ X] Associated with an issue (GitHub or internal)