rename convert to config to align with compose v1 UX

[ndeloof]

What I did
renamed "convert" command to "config" to be aligned with Compose V1 UX
convert was introduced by Cloud integration development as we translated the compose model into cloud provider custom format. It was later adopted as the basis for compose config implementation, but changing the command canonical name doesn't make sense for our users (thousands blogs, stackoverflow, ... mention use of config command)

[codecov]

Codecov Report

Base: 73.89% // Head: 73.89% // No change to project coverage 👍

Coverage data is based on head (b695ece) compared to base (97752b2).
Patch has no changes to coverable lines.

❗ Current head b695ece differs from pull request most recent head b723790. Consider uploading reports for the commit b723790 to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##               v2   #10214   +/-   ##
=======================================
  Coverage   73.89%   73.89%           
=======================================
  Files           2        2           
  Lines         272      272           
=======================================
  Hits          201      201           
  Misses         60       60           
  Partials       11       11           

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[glours]

LGTM