Unnecessary param in `mlem create deployment`

[aguschin]

If you already created an env, why you should specify this again when creating deploy? Example:

$ mlem create env heroku staging  # note HEROKU
💾 Saving env to staging.mlem

$ mlem create deployment heroku myservice -c app_name=mlem-quick-start -c model=rf -c env=staging  # HEROKU again
💾 Saving deployment to myservice.mlem

Seems like unnecessary duplication, but maybe I'm missing something.

[aguschin]

related to #233

[jorgeorpinel]

May be related to #267 as well.

[aguschin]

May be fixed by #363

[mike0sv]

It will be partly fixed. It will allow to skip env entirely, but if you want to set up some env params, you will probably still need to specify env type