Bump actions/checkout from 5 to 6 (#16)

Author: dependabot[bot]

.github/workflows/coverage.yml

@@ -15,7 +15,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Cache dependencies
         uses: actions/cache@v4

.github/workflows/tests.yml

@@ -36,7 +36,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Cache dependencies
         uses: actions/cache@v4