Build ostools image on PR as well

Signed-off-by: Itxaka <itxaka@kairos.io>

.github/workflows/tool-image.yml

@@ -2,6 +2,7 @@
 name: 'build tools container images'
 
 on:
+  pull_request:
   push:
     branches:
       - master
@@ -54,8 +55,18 @@ jobs:
           registry: quay.io
           username: ${{ secrets.QUAY_USERNAME }}
           password: ${{ secrets.QUAY_PASSWORD }}
-
       - name: Build
+        if: github.event_name == 'pull_request'
+        uses: docker/build-push-action@v5
+        with:
+          builder: ${{ steps.buildx.outputs.name }}
+          context: ./tools-image
+          file: ./tools-image/Dockerfile
+          platforms: linux/amd64,linux/arm64
+          push: false
+          tags: ${{ steps.prep.outputs.tags }}
+      - name: Build and push
+        if: github.event_name != 'pull_request'
         uses: docker/build-push-action@v5
         with:
           builder: ${{ steps.buildx.outputs.name }}