Change artifact directory structure

.github/workflows/maven.yml

@@ -24,9 +24,12 @@ jobs:
         restore-keys: ${{ runner.os }}-m2
     - name: Build with Maven
       run: mvn -B package
+    - name: Stage build artifacts
+      run: |
+        mkdir staging
+        cp server/target/envoy-server-jar-with-dependencies.jar staging/envoy-server.jar
+        cp client/target/envoy-client*shaded.jar staging/envoy.jar
     - uses: actions/upload-artifact@v2
       with:
         name: envoy-${{ matrix.os }}
-        path: |
-          server/target/envoy-server-jar-with-dependencies.jar
-          client/target/envoy-client*shaded.jar
+        path: staging