Duplicated progress env var

[crazy-max]

This PR reverts BUILDX_PROGRESS_DEFAULT env var that was introduced in #504 because it was already available through #69 with BUILDKIT_PROGRESS env var.

Docs have also been updated as stipulated in #62 (comment)

Signed-off-by: CrazyMax crazy-max@users.noreply.github.com

[thaJeztah]

LGTM, looks like it was not yet in use by anyone 🤞https://grep.app/search?q=BUILDX_PROGRESS_DEFAULT

[crazy-max]

@thaJeztah

looks like it was not yet in use by anyone

Yes hopefully :)

[thaJeztah]

Perhaps we should add a section related to build env-vars in https://github.com/docker/cli/blob/master/docs/reference/commandline/cli.md#environment-variables

(also make sure that docker build without buildx supports this)

[crazy-max]

@thaJeztah

Perhaps we should add a section related to build env-vars

Done docker/cli#3208

I think we should also mutualize the progress package in a follow-up:

• https://github.com/docker/buildx/tree/master/util/progress
• https://github.com/moby/buildkit/tree/master/util/progress

[thaJeztah]

I think we should also mutualize the progress package in a follow-up:

Possibly yes; but I see the buildkit version has more subpackages. Haven't looked closely yet, but if you do so, be sure check that it doesn't bring complexity and/or dependencies that are not desirable here.