jenkins: leaf-build: Delete prebuilt boot/recovery images before signing

* Otherwise prebuilts get picked up directly without any re-signing

Change-Id: I1b917c39d60d45176404ea3fe01dd4043d656c44
1 file changed
tree: 444f2c8b1e1d77461ece46a64f3f8b0e45e226ff
  1. jenkins/