Bump to dotnet/android-tools@c8b05f6 (#1370)

Bumps [external/xamarin-android-tools](https://github.com/xamarin/xamarin-android-tools) from `8722663` to `c8b05f6`.
- [Commits](dotnet/android-tools@8722663...c8b05f6)

---
updated-dependencies:
- dependency-name: external/xamarin-android-tools
  dependency-version: c8b05f6dce08076758f28825ed261b92cf51b491
  dependency-type: direct:production
...

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