refactor: Delete unused REST handler for VPP commands

[rewenset]

That handler:

func (p *Plugin) commandHandler(formatter *render.Render) http.HandlerFunc {

was moved to govppmux in this PR: #1593.

And from that point (after the PR was merged), new home for the handler is here:

vpp-agent/plugins/govppmux/rest.go

Line 58 in 6ba0dbb

func (p *Plugin) cliCommandHandler(formatter *render.Render) http.HandlerFunc {

[rewenset]

(it is a screenshot, do not click on link)

😮

[codecov]

Codecov Report

Merging #1677 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1677   +/-   ##
=======================================
  Coverage   58.07%   58.07%           
=======================================
  Files         366      366           
  Lines       30045    30045           
=======================================
  Hits        17450    17450           
  Misses      11155    11155           
  Partials     1440     1440           

Flag	Coverage Δ
#unittests	58.07% <ø> (ø)