Update Golang version to v1.19 for branch main

[blackpiglet]

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Fixes #(issue)

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[blackpiglet]

Still cannot workaround the VSC error without adding the -buildvcs=falseflag into the code-generator's script.

error obtaining VCS status: exit status 128
	Use -buildvcs=false to disable VCS stamping.

I created an issue in the code-generator repository to ask for some help.
https://github.com/kubernetes/code-generator/issues/156

The sed command is removed, by checkout code-generator git repository in the update CRD script.

[codecov-commenter]

Codecov Report

Merging #6039 (42ec721) into main (491664e) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #6039   +/-   ##
=======================================
  Coverage   41.32%   41.32%           
=======================================
  Files         251      251           
  Lines       23375    23375           
=======================================
  Hits         9660     9660           
  Misses      12957    12957           
  Partials      758      758           

Impacted Files	Coverage Δ
pkg/cmd/server/server.go	5.19% <ø> (ø)

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[reasonerjt]

LGTM