CI: bump actions/checkout from 5 to 6 (#8)

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ jobs:
     name: Check formatting
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 1
       - name: Set up Go
@@ -31,7 +31,7 @@ jobs:
     name: Run linters
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 1
       - name: Set up Go
@@ -50,7 +50,7 @@ jobs:
     name: Run tests
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 1
       - name: Set up Go

.github/workflows/release.yml

@@ -14,7 +14,7 @@ jobs:
       packages: write
       contents: write
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 1
       - name: Set up Go