cli/command: remove NotaryClient from CLI interface

[thaJeztah]

• relates to cli/command: internalize and deprecate Cli.NotaryClient #5885
• relates to cli/command: deprecate Cli.ManifestStore, Cli.RegistryClient #5889
• relates to vendor: github.com/docker/cli buildx#3033

cli/command: remove deprecated NotaryClient from CLI interface

This method is a shallow wrapper around trust.GetNotaryRepository, but
due to its signature resulted in the trust package, and notary dependencies
to become a dependency of the CLI. Consequence of this was that cli-plugins,
which need the cli/command package, would also get notary and its
dependencies as a dependency. It is no longer used, and was deprecated
in 9bc16bb.

This patch removes the NotaryClient method from the interface

cli/command: remove deprecated ManifestStore from CLI interface

This method is a shallow wrapper around manifeststore.NewStore, but
due to its signature resulted in various dependencies becoming a dependency
of the "command" package. Consequence of this was that cli-plugins, which
need the cli/command package, would also get those dependencies. It is no
longer used, and was deprecated in e32d5d5.

This patch removes the ManifestStore method from the interface

cli/command: remove deprecated RegistryClient from CLI interface

This method was a shallow wrapper around registryclient.NewRegistryClient but
due to its signature resulted in various dependencies becoming a dependency
of the "command" package. Consequence of this was that cli-plugins, which
need the cli/command package, would also get those dependencies. It is no
longer used, and was deprecated in 8ad0721.

This patch removes the RegistryClient method from the interface

- Human readable description for the release notes

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[codecov-commenter]

Codecov Report

Attention: Patch coverage is 7.86517% with 164 lines in your changes missing coverage. Please review.

Project coverage is 59.25%. Comparing base (e558b91) to head (bb474a6).

❌ Your patch status has failed because the patch coverage (7.86%) is below the target coverage (50.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5876      +/-   ##
==========================================
- Coverage   59.28%   59.25%   -0.03%     
==========================================
  Files         355      356       +1     
  Lines       29758    29776      +18     
==========================================
+ Hits        17643    17645       +2     
- Misses      11143    11158      +15     
- Partials      972      973       +1     

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[thaJeztah]

This is a difference; before this, we would take the Err() output from the CLI, and now we switched to the Cobra cmd's StdErr() - we should look in our code altogether to consider using that (instead of depending on the DockerCLI to provide us the stderr/stdout; I think they're coupled either way.