changing back to ubuntu runner for arm build (mac runners apparently don't have Docker preinstalled

Signed-off-by: Will Dower <will@dower.dev>

Author: wdower

.github/workflows/push-server-to-docker.yml

@@ -31,7 +31,7 @@ jobs:
           cache-to: type=gha,mode=max,scope=amd64
 
   build-arm64:
-    runs-on: macos-14
+    runs-on: ubuntu-24.04
     steps:
       - name: Checkout the Heimdall Repository
         uses: actions/checkout@v5