Update firmware_build.yml

.github/workflows/firmware_build.yml

@@ -8,9 +8,9 @@ on:
 jobs:
   build_firmware:
     name: RHC-internal-Z4
-#    runs-on: self-hosted
+    runs-on: self-hosted
     name: Build firmware on GitHub using latest Ubuntu
-    runs-on: ubuntu-latest
+#    runs-on: ubuntu-latest
     
     steps:
       - name: Check out code from GitHub