Bump subosito/flutter-action from 2.16.0 to 2.21.0

Bumps [subosito/flutter-action](https://github.com/subosito/flutter-action) from 2.16.0 to 2.21.0.
- [Release notes](https://github.com/subosito/flutter-action/releases)
- [Commits](subosito/flutter-action@44ac965...fd55f4c)

---
updated-dependencies:
- dependency-name: subosito/flutter-action
  dependency-version: 2.21.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/code-analysis.yml

@@ -23,7 +23,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-      - uses: subosito/flutter-action@44ac965b96f18d999802d4b807e3256d5a3f9fa1 # v2.16.0
+      - uses: subosito/flutter-action@fd55f4c5af5b953cc57a2be44cb082c8f6635e8e # v2.21.0
         with:
           flutter-version: ${{ env.FLUTTER_VERSION }}
           cache: true

.github/workflows/test.yml

@@ -47,7 +47,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-      - uses: subosito/flutter-action@44ac965b96f18d999802d4b807e3256d5a3f9fa1 # v2.16.0
+      - uses: subosito/flutter-action@fd55f4c5af5b953cc57a2be44cb082c8f6635e8e # v2.21.0
         with:
           flutter-version: ${{ env.FLUTTER_VERSION }}
           cache: true
@@ -126,7 +126,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-      - uses: subosito/flutter-action@44ac965b96f18d999802d4b807e3256d5a3f9fa1 # v2.16.0
+      - uses: subosito/flutter-action@fd55f4c5af5b953cc57a2be44cb082c8f6635e8e # v2.21.0
         with:
           flutter-version: ${{ matrix.flutter-version }}
           cache: true