Bump external/xamarin-android-tools from 099fd95 to 3b8c467 (#1109)

Bumps [external/xamarin-android-tools](https://github.com/xamarin/xamarin-android-tools) from `099fd95` to `3b8c467`.
- [Commits](dotnet/android-tools@099fd95...3b8c467)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]