.github/workflows/build.yml: drop pull_request_target

This still runs CI twice in a PR.

Signed-off-by: Sergii Dmytruk <sergii.dmytruk@3mdeb.com>

Author: SergiiDmytruk

.github/workflows/build.yml

@@ -6,9 +6,6 @@ on:
       - 'aem*'
     tags:
       - '*'
-  pull_request_target:
-    branches: # this is to avoid running the workflow twice in a PR
-      - 'aem*'
 
 jobs:
   qubes-dom0-package: