chore: remove deprecated konnect subcommands

[voigtjr]

The deprecated konnect subcommands rely on the deactivated konnect.konghq.com domain and is now broken because of that. These changes remove the deprecated subcommands.

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[codecov-commenter]

Codecov Report

Patch coverage has no change and project coverage change: +0.93 🎉

Comparison is base (7189614) 35.57% compared to head (e549d9a) 36.51%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #910      +/-   ##
==========================================
+ Coverage   35.57%   36.51%   +0.93%     
==========================================
  Files          92       87       -5     
  Lines       11279    10991     -288     
==========================================
  Hits         4013     4013              
+ Misses       6873     6585     -288     
  Partials      393      393              

Impacted Files	Coverage Δ
cmd/common_konnect.go	11.04% <ø> (+4.33%)	⬆️
cmd/root.go	0.00% <ø> (ø)

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[Tieske]

should this be targeted at the v2 branch? see #941