Ability to watch for dependent service rebuilds

[mikesir87]

Description

I have a Compose file that builds multiple services, one of which ends up being an additional context for the other. Like this:

services:
  service1:
    build: ./components/service1
  service2:
    build: ./components/service2
    additional_contexts:
      service1: service:service1

While I can add Compose Watch config to service1 and have it rebuild, there's no mechanism available to trigger a rebuild of service2.

Therefore, it would be nice to have a mechanism that would allow me to rebuild/restart service2 when a rebuild of service1 has occurred.