chore(deps): update actions/upload-artifact action to v7

Author: renovate[bot]

.github/workflows/build-and-test.yml

@@ -60,7 +60,7 @@ jobs:
 
     - name: Upload test artifacts on failure
       if: failure()
-      uses: actions/upload-artifact@v6
+      uses: actions/upload-artifact@v7
       with:
         name: test-results
         path: |

.github/workflows/publish-nuget.yml

@@ -147,14 +147,14 @@ jobs:
         done
 
     - name: Upload packages as artifacts
-      uses: actions/upload-artifact@v6
+      uses: actions/upload-artifact@v7
       with:
         name: nuget-packages
         path: ./artifacts/*.nupkg
         retention-days: 30
 
     - name: Upload symbol packages as artifacts
-      uses: actions/upload-artifact@v6
+      uses: actions/upload-artifact@v7
       if: always()
       with:
         name: symbol-packages