ci: copy pr2 artifacts

Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>

Author: gmarull

.github/workflows/build.yml

@@ -49,6 +49,8 @@ jobs:
 
           cp twister-out/pt2*/zephyr/pblboot/boot/boot.default/zephyr/zephyr.hex \
              artifacts/pblboot-pt2-$VERSION.hex
+          cp twister-out/pr2*/zephyr/pblboot/boot/boot.default/zephyr/zephyr.hex \
+             artifacts/pblboot-pr2-$VERSION.hex
 
       - name: Store artifacts
         uses: actions/upload-artifact@v4