Update build.yml

Author: haochengxia

.github/workflows/build.yml

@@ -47,6 +47,7 @@ jobs:
 
   selfhosted:
     runs-on: self-hosted
+    if: github.repository == '1a1a11a/libCacheSim'
     steps:
       - uses: actions/checkout@v4
       - name: Configure CMake