Fix iOS CI config

Author: Kyle-Ye

.github/workflows/ios.yml

@@ -34,7 +34,15 @@ jobs:
           xcode-version: ${{ matrix.xcode-version }}
       - name: Swift version
         run: swift --version
-      - name: Build and run tests in debug mode
+      - name: Build test target in debug mode
+        run: |
+          xcodebuild build \
+            -scheme OpenSwiftUITests \
+            -configuration Debug \
+            -destination "platform=iOS Simulator,OS=${{ matrix.ios-version }},name=${{ matrix.ios-simulator-name }}" \
+            -skipMacroValidation \
+            -skipPackagePluginValidation
+      - name: Run test target in debug mode
         run: |
           xcodebuild test \
             -scheme OpenSwiftUITests \