chore(deps): update actions/checkout digest to 9b4c13b (#411)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| actions/checkout | action | digest | `1d96c77` -> `9b4c13b` |

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.github/workflows/ci.yml

@@ -192,7 +192,7 @@ jobs:
     env:
       CC: clang
     steps:
-      - uses: actions/checkout@1d96c772d19495a3b5c517cd2bc0cb401ea0529f
+      - uses: actions/checkout@9b4c13b0bfa31b4514c14f74b5a166c2708f43c6
       - uses: cgrindel/gha_set_up_bazel@v1
         with:
           bazel_disk_cache_dir: ""
@@ -218,7 +218,7 @@ jobs:
           - ubuntu-22.04
     runs-on: ${{ matrix.runner }}
     steps:
-      - uses: actions/checkout@1d96c772d19495a3b5c517cd2bc0cb401ea0529f
+      - uses: actions/checkout@9b4c13b0bfa31b4514c14f74b5a166c2708f43c6
       - uses: cgrindel/gha_set_up_bazel@v1
         with:
           bazel_disk_cache_dir: ""