gha : Revert clang-format and cmake-format on PR

When using these workflows on PR, the following error message is displayed
Error: When the repository is checked out on a commit instead of a branch, the 'base' input must be supplied.

.github/workflows/clang-format.yml

@@ -1,6 +1,6 @@
 name: clang-format
 
-on: [push, pull_request]
+on: [push]
 
 jobs:
   clang-format-job:

.github/workflows/cmake-format.yml

@@ -1,6 +1,6 @@
 name: cmake-format
 
-on: [push, pull_request]
+on: [push]
 
 jobs:
   cmake-format-job: