Use docker image for Swift 5.9

Author: kateinoigakukun

.github/workflows/deploy.yml

@@ -7,12 +7,10 @@ on:
 jobs:
   build:
     runs-on: ubuntu-latest
+    container: swift:5.9-focal
 
     steps:
       - uses: actions/checkout@v4
-      - uses: swift-actions/setup-swift@v1
-        with:
-          swift-version: '5.9'
       - run: swift run SwiftWasmBlog
       - uses: actions/upload-pages-artifact@v3
         with: