R4R: Fix validator address encoding in tm validator set command

[alexanderbez]

• Use consensus address bech32 prefixing
• Use CLIContext#PrintOutput

closes: #3501

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• Linked to github-issue with discussion and accepted design OR link to spec that describes this work.

• Wrote tests

• Updated relevant documentation (docs/)

• Added entries in PENDING.md with issue #

• rereviewed Files changed in the github PR explorer

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[jackzampolin]

Theres a failing LCD test here.

[alexanderbez]

@jackzampolin fixed

[codecov]

Codecov Report

Merging #3504 into develop will decrease coverage by 1.91%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           develop    #3504      +/-   ##
===========================================
- Coverage    54.89%   52.97%   -1.92%     
===========================================
  Files          141      142       +1     
  Lines        10426    10363      -63     
===========================================
- Hits          5723     5490     -233     
- Misses        4357     4550     +193     
+ Partials       346      323      -23