Wait before proceed parameter

[coders-kitchen]

I realized today that some containers need a separate wait step before the checks for port or log line could be executed.

For example the official postgres container restarts postgres once, to enable some settings.

This change introduces the parameter waitBeforeProceed which, if set, waits the specified time before the other checks are executed.

[geowarin]

Hey @coders-kitchen.
Thanks for your PR !

Looking at test-containers, they have a better dsl that they use to wait for events:

https://github.com/testcontainers/testcontainers-java/blob/56513a44e21d21dc15d14416806775b80c252efd/modules/postgresql/src/main/java/org/testcontainers/containers/PostgreSQLContainer.java#L26-L29

I think I'll try to implement something like this, what do you think ?
It seems better than waiting for an empirical duration.