flags: hidden not stable command flags

[3pointer]

No description provided.

[codecov]

Codecov Report

Merging #133 into master will decrease coverage by 1.11%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #133      +/-   ##
==========================================
- Coverage   74.08%   72.97%   -1.12%     
==========================================
  Files          35       33       -2     
  Lines        3886     3234     -652     
==========================================
- Hits         2879     2360     -519     
+ Misses        683      585      -98     
+ Partials      324      289      -35

Impacted Files	Coverage Δ
cmd/validate.go	67.62% <100%> (+0.13%)	⬆️
pkg/storage/gcs.go	71.96% <100%> (+0.8%)	⬆️
pkg/storage/s3.go	84.41% <100%> (+0.63%)	⬆️
cmd/backup.go	67.97% <100%> (-2.71%)	⬇️
pkg/restore/import.go	64.55% <0%> (-8.9%)	⬇️
pkg/backup/client.go	73.47% <0%> (-6.11%)	⬇️
cmd/restore.go	64.34% <0%> (-2.68%)	⬇️
pkg/restore/client.go	72.9% <0%> (-1.24%)	⬇️
pkg/utils/keys.go
... and 1 more

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[overvenus]

Could you hidden validate subcommand too?

[overvenus]

LGTM