Point to gallery workflow in Windows deployment docs (#8605)

Updates the example URL for an MSIX release workflow to that in Flutter
Gallery.

## Presubmit checklist
- [x] This PR doesn’t contain automatically generated corrections
(Grammarly or similar).
- [x] This PR follows the [Google Developer Documentation Style
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- [x] This PR uses [semantic line
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Author: yaakovschectman

src/deployment/windows.md

@@ -141,7 +141,7 @@ in a GitHub Action packages the
 application into an MSIX and uploads it to a new submission on the dev center.
 
 An example Action YAML file for continuous deployment can be found
-[within a dedicated repository](https://github.com/yaakovschectman/SampleFlutterMSIXGithubAction/blob/main/dart.yml).
+[in the Flutter Gallery](https://github.com/flutter/gallery/blob/main/.github/workflows/release_deploy_windows.yml).
 The steps necessary for MSIX publishing are excerpted below:
 
 ```