docs/api: update /containers/{id}/wait "condition" parameter (v1.30-v1.41)
This patch updates the swagger, and:
- adds an enum definition to document valid values (instead of describing them)
- updates the description to mention both "omitted" and "empty" values (although
the former is already implicitly covered by the field being "optional" and
having a default value).
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>