Integrate Glean SDK

[cketti]

• [ ] Add dependency (only to Thunderbird for Android)
• [ ] Initialize SDK (after settings have been loaded)
  • [ ] Manually configure the build info (since we won't be using the Gradle plugin at first)
  • [ ] Configure the release channel
• [ ] Make sure uploads are disabled when telemetry has been disabled via the app setting
• [ ] Make sure the initialization only happens after the app locale has been set

Depends on

• #8088
• #8089