ci: Fix macos publish by specifying swift version

Author: NeedleInAJayStack

.github/workflows/publish.yaml

@@ -16,6 +16,8 @@ jobs:
         uses: actions/checkout@v4
       - name: Set up Swift
         uses: swift-actions/setup-swift@v2
+        with:
+          swift-version: "6"
       - name: Build
         run: swift build --configuration release
       - name: Archive binary