revert gh action

.github/workflows/build_wheel.yml

diff --git a/.github/workflows/build_wheel.yml b/.github/workflows/build_wheel.yml
index 29ff31e..bb853f5 100644
--- a/.github/workflows/build_wheel.yml
+++ b/.github/workflows/build_wheel.yml
@@ -16,7 +16,6 @@
 name: Build wheels
 
 on:
-  pull_request:
   push:
     branches:
       - master