Update actions/setup-dotnet action to v6

.gitea/workflows/merge.yaml

@@ -23,7 +23,7 @@ jobs:
       - name: Print execution time
         run: echo "Time ${{ steps.adocbuild.outputs.time }}"
       - name: Upload artifact
-        uses: actions/upload-artifact@v7
+        uses: actions/upload-artifact@v6
         with:
             name: Doc
             path: ./docs

.gitea/workflows/review.yaml

@@ -15,7 +15,7 @@ jobs:
     - name: Checkout code
       uses: actions/checkout@v6
     - name: Setup dotnet
-      uses: actions/setup-dotnet@v3
+      uses: actions/setup-dotnet@v6
       with:
         dotnet-version: '8.0.x'
     - name: Install dependencies