Use v4 of upload-artifact

Author: patri9ck

.github/workflows/build.yml

@@ -19,7 +19,7 @@ jobs:
       - name: Build APK
         run: ./gradlew clean assembleDebug
       - name: Upload artifact
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: apk
           path: app/build/outputs/apk/debug/app-debug.apk