add cache-after-prepare: true

.github/workflows/Omnios.yml

@@ -64,6 +64,7 @@ jobs:
     - uses: vmactions/omnios-vm@v1
       with:
         debug-on-error: ${{ vars.DEBUG_ON_ERROR }}
+        cache-after-prepare: true
         envs: 'TEST_LOCAL TestingDomain TEST_ACME_Server CA_ECDSA CA CA_EMAIL TEST_PREFERRED_CHAIN ACME_USE_WGET'
         nat: |
           "8080": "80"