break-pacman-upload-lease: do not skip it

Apparently we do not get the correct
`github.event.repository.owner.login` when dispatching a workflow run...

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

.github/workflows/break-pacman-upload-lease.yml

@@ -6,7 +6,7 @@ on:
 
 jobs:
   break-lease:
-    if: github.event.repository.owner.login == 'git-for-windows'
+    if: github.repository.fork == false
     runs-on: ubuntu-latest
     steps:
       - name: Clone build-extra