ci: use ubuntu-22.04 and remove cache

Author: WasinWatt

.github/workflows/docker.yml

@@ -25,7 +25,7 @@ env:
 jobs:
   opinitd:
     name: opinitd
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
 
     permissions:
       contents: read
@@ -68,5 +68,3 @@ jobs:
           platforms: linux/amd64,linux/arm64
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
-          cache-from: type=gha
-          cache-to: type=gha