Update swift.yml

Signed-off-by: Joe Maghzal <[email protected]>

Author: SwiftyJoeyy

.github/workflows/swift.yml

@@ -19,6 +19,8 @@ jobs:
       with:
         xcode-version: latest-stable
     - uses: swift-actions/setup-swift@v2
+      with:
+        swift-version: "6.0"
     - uses: actions/checkout@v4
     - name: Build
       run: swift build -v