Fix #13

Signed-off-by: Nick Slowinski <nick@nick-slowinski.de>

.forgejo/workflows/build.yaml

@@ -4,6 +4,9 @@ on:
     branches:
       - !'main'
       - '*'
+  pull_request:
+    types: [opened, synchronize, reopened]
+  
 jobs:
   build:
     runs-on: docker