Update actions/checkout digest to b4ffde6 (#354)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/test.yml

@@ -13,7 +13,7 @@ jobs:
         node: [ '18.12.1' ]
     name: Node ${{ matrix.node }}
     steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
+      - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4
       - uses: actions/setup-node@v3
         with:
           node-version: ${{ matrix.node }}