housekeeping: Update version and fix nullability issues (reactiveui#2738

)

* housekeeping: Change the non-package repos

* housekeeping: Update versions and fix nullability issues

fix: Update nullability, pick dependencies (reactiveui#2720)

* build(deps): bump Xamarin.AndroidX.Fragment in /src

Bumps [Xamarin.AndroidX.Fragment](https://github.com/xamarin/AndroidX) from 1.3.0.1 to 1.3.1.
- [Release notes](https://github.com/xamarin/AndroidX/releases)
- [Commits](https://github.com/xamarin/AndroidX/commits)

Signed-off-by: dependabot[bot] <[email protected]>

* build(deps): bump DiffEngine from 6.5.7 to 6.6.1 in /src

Bumps [DiffEngine](https://github.com/VerifyTests/DiffEngine) from 6.5.7 to 6.6.1.
- [Release notes](https://github.com/VerifyTests/DiffEngine/releases)
- [Commits](VerifyTests/DiffEngine@6.5.7...6.6.1)

Signed-off-by: dependabot[bot] <[email protected]>

* build(deps): bump Acr.UserDialogs in /integrationtests

Bumps [Acr.UserDialogs](https://github.com/aritchie/userdialogs) from 7.1.0.481 to 7.1.0.483.
- [Release notes](https://github.com/aritchie/userdialogs/releases)
- [Commits](https://github.com/aritchie/userdialogs/commits)

Signed-off-by: dependabot[bot] <[email protected]>

* build(deps): bump Fody from 6.4.0 to 6.5.0 in /src

Bumps [Fody](https://github.com/Fody/Fody) from 6.4.0 to 6.5.0.
- [Release notes](https://github.com/Fody/Fody/releases)
- [Commits](Fody/Fody@6.4.0...6.5.0)

Signed-off-by: dependabot[bot] <[email protected]>

* build(deps): bump FodyPackaging from 6.4.0 to 6.5.0 in /src

Bumps [FodyPackaging](https://github.com/Fody/Fody) from 6.4.0 to 6.5.0.
- [Release notes](https://github.com/Fody/Fody/releases)
- [Commits](Fody/Fody@6.4.0...6.5.0)

Signed-off-by: dependabot[bot] <[email protected]>

* build(deps): bump FodyHelpers from 6.4.0 to 6.5.0 in /src

Bumps [FodyHelpers](https://github.com/Fody/Fody) from 6.4.0 to 6.5.0.
- [Release notes](https://github.com/Fody/Fody/releases)
- [Commits](Fody/Fody@6.4.0...6.5.0)

Signed-off-by: dependabot[bot] <[email protected]>

* Command binder nullability hint

* Fix a few more nullability issues

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

housekeeping: Change the non-package repos (reactiveui#2698)

housekeeping: Release RxUI 13.1.x (reactiveui#2656)

housekeeping: Upgraded Xamarin.Forms to v4.8 (reactiveui#2640)

housekeeping: Remove cast (reactiveui#2626)

* housekeeping: Remove cast

* Fix approvals

* Fix approval tests again

* Fix

housekeeping: Release 13.0.x (reactiveui#2598)

fix: TransitionContentControl throwing exception on control height ze…

…ro (reactiveui#2569)

housekeeping: Release 12.1 (reactiveui#2563)

Fix/memory leaks (reactiveui#2504)

* Fix: WhenActivated-binding memory leak

- The ReactiveBinding.ViewModel property gets initialized when a binding is created, but never updated if the view model gets swapped out for another. This means the initial view model gets tied to the lifetime of the binding.

* Fix: SubscribeToExpressionChain memory leak

- If the initial view model is not null (before binding, etc) that view model is never grabage collected even it's swapped out for a different one.