composer server destroy returns an error if docker proxy server is in use

[jazzsequence]

It may not be possible to silence this error, but it is an error that shows up when you run composer server destroy on a machine that is using other Altis local server instances.

Steps to reproduce:

1. Create multiple Altis environments
2. Make sure that both have run composer serve at least once each (so the containers are set up)
3. run composer server destroy on one of the environments
4. see error in terminal

Expected behavior:
No error displays after destroy command is run.

Acceptance criteria:

• ...