Pin ubuntu version in workflow

Author: sunnamed434

.github/workflows/RocketModFix.UnityEngine.Redist.yaml

@@ -9,7 +9,7 @@ on:
 jobs:
   build:
     name: "RocketModFix.UnityEngine.Redist Pack"
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
     - uses: actions/checkout@v6
     - uses: actions/setup-dotnet@v5