chore(deps): update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/buildifier.yaml

@@ -12,6 +12,6 @@ jobs:
   check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: buildifier
         run: bazel run --enable_bzlmod //.github/workflows:buildifier.check

.github/workflows/ci.yaml

@@ -30,7 +30,7 @@ jobs:
   pre-commit:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: pre-commit/action@v3.0.1
   # For branch protection settings, this job provides a "stable" name that can be used to gate PR merges
   # on "all matrix jobs were successful".

.github/workflows/tag.yaml

@@ -22,7 +22,7 @@ jobs:
       new-tag-version-type: ${{ steps.ccv.outputs.new-tag-version-type }}
       recently-tagged: ${{ steps.recent-tag.outputs.recently-tagged }}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           # Need enough history to find the prior release tag
           fetch-depth: 0