build(deps): bump actions/checkout from 6 to 7

Bumps [actions/checkout](https://github.com/actions/checkout) from 6 to 7.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v6...v7)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -13,7 +13,7 @@ jobs:
   ci:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - uses: subosito/flutter-action@v2
         with:

.github/workflows/deploy.yml

@@ -21,7 +21,7 @@ jobs:
     needs: ci
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - uses: subosito/flutter-action@v2
         with:

.github/workflows/preview.yml

@@ -12,7 +12,7 @@ jobs:
   preview:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - uses: subosito/flutter-action@v2
         with:

.github/workflows/rollback.yml

@@ -21,7 +21,7 @@ jobs:
   rollback:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
         with:
           ref: ${{ inputs.ref }}