Updated actions on macOS to use setup-xcode

Author: d-exclaimation

.github/workflows/test.yml

@@ -6,16 +6,29 @@ on:
   pull_request:
     branches: [ master ]
 jobs:
-  build:
+  linux-build:
     name: Build and test on ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [macos-latest, ubuntu-latest]
+        os: [ubuntu-latest]
     steps:
       - uses: actions/checkout@v2
       - uses: swift-actions/setup-swift@v1
       - name: Build
         run: swift build
       - name: Run tests
         run: swift test
+  macos-build:
+    name: Build and test on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [macos-latest]
+    steps:
+      - uses: actions/checkout@v2
+      - uses: maxim-lobanov/setup-xcode@v1
+      - name: Build
+        run: swift build
+      - name: Run tests
+        run: swift test