ci-artifacts: run the pipeline if owner is git-for-windows

In a previous commit, we incorrectly added logic to only run this job if the repo is not a fork. However, git-sdk-arm64 is a fork of git-sdk-64, so this doesn't hold!

Let's switch to checking the repository owner instead, which should be good enough.

Signed-off-by: Dennis Ameling <[email protected]>

.github/workflows/ci-artifacts.yml

@@ -15,7 +15,7 @@ env:
 
 jobs:
   minimal-sdk-artifact:
-    if: github.event.repository.fork == false
+    if: github.repository_owner == 'git-for-windows'
     runs-on: [Windows, ARM64]
     steps:
       - name: clone git-sdk-arm64