Upgrade to actions/upload-artifact@v4

Author: R1tschY

.github/workflows/build.yml

@@ -56,7 +56,8 @@ jobs:
           enable-debug: true
 
       - name: Upload build result
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         with:
           name: sailfishconnect-${{ matrix.arch }}
           path: RPMS
+          compression-level: 0