Update actions/checkout action to v7

| datasource  | package          | from | to     |
| ----------- | ---------------- | ---- | ------ |
| github-tags | actions/checkout | v6   | v7.0.1 |

Author: renovate[bot]

.github/workflows/continuous-integration.yml

@@ -52,7 +52,7 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v6"
+        uses: "actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1" # v7
         with:
           fetch-depth: 0
 
@@ -103,7 +103,7 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v6"
+        uses: "actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1" # v7
         with:
           fetch-depth: 0
 

.github/workflows/release-on-milestone-closed.yml

@@ -14,7 +14,7 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v6"
+        uses: "actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1" # v7
 
       - name: "Release"
         uses: "laminas/automatic-releases@v1"