Update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/ci.yml

@@ -23,7 +23,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+        uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6
         with:
           fetch-depth: 0
 

.github/workflows/dependency-graph.yml

@@ -14,7 +14,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+        uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6
         with:
           fetch-depth: 0