Bump hard fd limit

Author: cgwalters

.github/actions/bootc-ubuntu-setup/action.yml

@@ -79,3 +79,6 @@ runs:
         sudo install -T ${target} /usr/bin/bcvk
         cd -
         rm -rf "$td"
+
+        # Also bump the default fd limit as a workaround for https://github.com/bootc-dev/bcvk/issues/65
+        sed -i -e 's,^\* hard nofile 65536,* hard nofile 524288,' limits.conf