Make `namespace` optional in plugin definitions, auto-generate if missing
As of now, it feels like we could confidently calculate namespace
as plugin_name.replace("-", "_").lower()
or similar.
For reference: https://gitlab.com/meltano/meltano/blob/master/src%2Fmeltano%2Fcore%2Fbundle%2Fdiscovery.yml
Do we still need this as a required field in every plugin definition? When missing it seems to result in difficult to diagnose failure messages such as #3357 (comment 900121643).
cc @tayloramurphy and @DouweM, since I think each of you may have more history on this functionality and when/if we'd still want namespace as a distinct field.
cc @pandemicsyn - Logged here as discussed in our 1:1.
cc @pnadolny13 since you've been working on discovery.yml plugin definition aspects in meltano and the hub.
Edited by AJ Steers