Update devtool to use new development image
# Development container image (name:tag)
# This should be updated whenever we upgrade the development container.
# (Yet another step on our way to reproducible builds.)
-DEVCTR_IMAGE="fcuvm/dev:v14"
+DEVCTR_IMAGE="fcuvm/dev:v15"
# Naming things is hard
MY_NAME="Firecracker $(basename "$0")"
