test: make test fails to run

[mmalenic]

Running make tests outputs an error when testing the sequence run manager:

Error response from daemon: Ports are not available: exposing port TCP 0.0.0.0:5432 -> 0.0.0.0:0: listen tcp 0.0.0.0:5432: bind: address already in use

I think this is due to a similar concurrency error solved by #184. I.e. because tests run in parallel, and the stack is synthesized multiple times in the tests, make up tries to use the same port more than once, causing the error.