fix!: update gentx val pub key input parsing

[alexanderbez]

Description

• Ensure input parity of validator public key input between tx staking create-validator and gentx, i.e the correct input is the full JSON payload of the public key. e.g. {"@type":"/cosmos.crypto.ed25519.PubKey","key":"<base64 payload>"}
• Update CLI flag description.

closes: #9819

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[alexanderbez]

@AmauryM should this also be targeted against an 0.43rc branch? I'm not up to speed on the latest release workflow.

[codecov]

Codecov Report

Merging #9827 (853ed07) into master (36ab23a) will increase coverage by 0.06%.
The diff coverage is 92.53%.

@@            Coverage Diff             @@
##           master    #9827      +/-   ##
==========================================
+ Coverage   63.47%   63.54%   +0.06%     
==========================================
  Files         566      566              
  Lines       53107    53130      +23     
==========================================
+ Hits        33711    33760      +49     
+ Misses      17488    17462      -26     
  Partials     1908     1908              

Impacted Files	Coverage Δ
x/genutil/client/cli/gentx.go	0.00% <0.00%> (ø)
x/gov/client/cli/query.go	0.00% <0.00%> (ø)
x/gov/keeper/vote.go	90.32% <33.33%> (ø)
x/gov/abci.go	91.57% <75.00%> (ø)
x/gov/client/testutil/deposits.go	94.11% <97.53%> (-0.73%)	⬇️
x/genutil/client/testutil/suite.go	100.00% <100.00%> (ø)
x/gov/keeper/deposit.go	81.14% <100.00%> (ø)
x/staking/client/cli/flags.go	50.00% <100.00%> (ø)

[amaury1093]

makes sense to me

[amaury1093]

should this also be targeted against an 0.43rc branch? I'm not up to speed on the latest release workflow.

Yes, I think it'll be good. I added the backport label