fix(actions): add caching for Unreal Engine build artifacts in macOS workflow

.gitea/workflows/test-macos-build.yml

@@ -15,6 +15,19 @@ jobs:
           lfs: true
           fetch-depth: 0
       
+      # Cache Unreal Engine build artifacts to speed up builds
+      - name: Cache UE build artifacts
+        uses: actions/cache@v3
+        with:
+          path: |
+            ./Intermediate
+            ./DerivedDataCache
+            ./Saved/StagedBuilds
+          key: ${{ runner.os }}-ue-build-${{ hashFiles('LuckyWorld.uproject') }}-${{ hashFiles('Config/**/*.ini') }}
+          restore-keys: |
+            ${{ runner.os }}-ue-build-${{ hashFiles('LuckyWorld.uproject') }}-
+            ${{ runner.os }}-ue-build-
+            
       # Setup environment for build
       - name: Setup environment
         run: |