Add arg to tronctl retry for waiting for dependencies

[kawaiwanyelp]

Description

This PR gives tronctl retry a new option, --wait-for-deps that, if set, will make tronctl wait for all upstream triggers and required actions to complete before attempting to retry a given action. An arg can be passed to the option specifying a timeout, including "infinity" (i.e. never timeout), for how long to wait before giving up.

By default, the behavior of not waiting before retrying is preserved. However, I've made it so that even with the default timeout of 0 (i.e. don't want), we check to make sure all dependencies are done, because the current behavior is to issue a retry, to which the server will respond with an OK, even if the retry will fail anyway because dependencies are not done.

Testing

make test
manual testing on an example cluster, using a job with an action that has both upstream triggers and required actions

[nemacysts]

i mostly just have some nits that you can ignore if you'd like - but there are a couple questions in my review comments as well :)