Update actions/checkout action to v6 (#1315)

Author: renovate[bot]

.github/workflows/codeql-analysis.yml

@@ -18,7 +18,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
 
     - name: Install .NET SDK
       uses: actions/setup-dotnet@v5

.github/workflows/packages-ci.yml

@@ -17,7 +17,7 @@ jobs:
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
       with:
         fetch-depth: 0
 

.github/workflows/packages-pr.yml

@@ -13,7 +13,7 @@ jobs:
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
       with:
         fetch-depth: 0