Disable triggers for O2 linter workflow

This should really use pull_request, not pull_request_target.

Author: ktf

.github/workflows/o2-linter.yml

@@ -2,7 +2,7 @@
 # Find issues in O2 code
 name: O2 linter
 
-"on": [pull_request_target, push]
+#"on": [pull_request_target, push]
 permissions: {}
 env:
   BRANCH_MAIN: master