ci: don't cache vulkan sdk on mac, restore is broken

see jakoch/install-vulkan-sdk-action#558

Author: Firestar99

.github/workflows/ci.yaml

@@ -30,7 +30,9 @@ jobs:
         with:
           vulkan_version: 1.4.321.0
           install_runtime: true
-          cache: true
+          # cache restore on mac is broken
+          # see https://github.com/jakoch/install-vulkan-sdk-action/issues/558
+          cache: ${{ runner.os != 'macOS' }}
           stripdown: true
       - if: ${{ runner.os == 'Linux' }}
         name: Linux - Install native dependencies