Bump dart-lang/setup-dart from 1.5.0 to 1.5.1

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] <support@github.com>

.github/workflows/test-package.yml

@@ -23,7 +23,7 @@ jobs:
         sdk: [dev]
     steps:
       - uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744
-      - uses: dart-lang/setup-dart@d6a63dab3335f427404425de0fbfed4686d93c4f
+      - uses: dart-lang/setup-dart@8a4b97ea2017cc079571daec46542f76189836b1
         with:
           sdk: ${{ matrix.sdk }}
       - id: install
@@ -51,7 +51,7 @@ jobs:
         platform: [vm, chrome]
     steps:
       - uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744
-      - uses: dart-lang/setup-dart@d6a63dab3335f427404425de0fbfed4686d93c4f
+      - uses: dart-lang/setup-dart@8a4b97ea2017cc079571daec46542f76189836b1
         with:
           sdk: ${{ matrix.sdk }}
       - id: install