Invalidate brush when transform changed event is fired

[BAndysc]

What does the pull request do?

Brushes will be invalidated when their bound Transforms fire a Changed event.

What is the current behavior?

Brushes are not invalidated when their bound Transform is changed (not the property, but the inner matrix).

What is the updated/expected behavior with this PR?

Changes to bound transform will cause the brush to invalidate and redraw.

How was the solution implemented (if it's not obvious)?

Checklist

• [ ] Added unit tests (if possible)? how can I unit test it?
• [ ] Added XML documentation to any related classes?
• [ ] Consider submitting a PR to https://github.com/AvaloniaUI/avalonia-docs with user documentation

Breaking changes

n/a

Obsoletions / Deprecations

n/a

Fixed issues

Fixes #15097

[avaloniaui-bot]

You can test this PR using the following package version. 11.2.999-cibuild0046487-alpha. (feed url: https://nuget-feed-all.avaloniaui.net/v3/index.json) [PRBUILDID]

[maxkatz6]

Closing due to inactivity