attempt to fix runner

Author: laruence

.github/workflows/integrate.yml

@@ -8,7 +8,7 @@ on:
 jobs:
   matrix:
     name: "PHP"
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     strategy:
       matrix:
         PHP: ["7.0", "7.4", "8.0", "8.3", "8.4", "8.5"]