Bump dart-lang/setup-dart from 1.5.0 to 1.5.1 (dart-archive/stream_channel#96)

Bumps [dart-lang/setup-dart](https://github.com/dart-lang/setup-dart) from 1.5.0 to 1.5.1.
- [Release notes](https://github.com/dart-lang/setup-dart/releases)
- [Changelog](https://github.com/dart-lang/setup-dart/blob/main/CHANGELOG.md)
- [Commits](dart-lang/setup-dart@d6a63da...8a4b97e)

---
updated-dependencies:
- dependency-name: dart-lang/setup-dart
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

pkgs/stream_channel/.github/workflows/test-package.yml

@@ -23,7 +23,7 @@ jobs:
         sdk: [dev]
     steps:
       - uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608
-      - uses: dart-lang/setup-dart@d6a63dab3335f427404425de0fbfed4686d93c4f
+      - uses: dart-lang/setup-dart@8a4b97ea2017cc079571daec46542f76189836b1
         with:
           sdk: ${{ matrix.sdk }}
       - id: install
@@ -50,7 +50,7 @@ jobs:
         sdk: [2.19.0, dev]
     steps:
       - uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608
-      - uses: dart-lang/setup-dart@d6a63dab3335f427404425de0fbfed4686d93c4f
+      - uses: dart-lang/setup-dart@8a4b97ea2017cc079571daec46542f76189836b1
         with:
           sdk: ${{ matrix.sdk }}
       - id: install