Update cross_platform.yml

Author: panayang

.github/workflows/cross_platform.yml

@@ -4,13 +4,15 @@
     "push": {
       "branches": [
         "trunk",
+        "main",
         "v*.x",
         "ci/*"
       ]
     },
     "pull_request": {
       "branches": [
         "trunk",
+        "main",
         "v*.x"
       ]
     }