Update swift.yml

Author: maxoly

.github/workflows/swift.yml

@@ -15,7 +15,10 @@ jobs:
     runs-on: macos-latest
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
+    - uses: swift-actions/setup-swift@v1
+      with:
+        swift-version: "5.8.1"
     - name: Build
       run: swift build -v
     - name: Run tests