ci: migrate runs-on to ARC v2 runner labels

Update self-hosted runner labels to new ARC v2 scale set names.
See SylphxAI/platform: docs/CI-RUNNERS-ARCHITECTURE.md

Author: shtse8

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ on:
 
 jobs:
   ci:
-    runs-on: [self-hosted, linux, x64]
+    runs-on: sylphx-linux-standard
     steps:
       - uses: actions/checkout@v4