Update Staking Validators Rest Query

[alexanderbez]

Support pagination and bond status query params in the /staking/validators REST endpoint. The default number of validators returned is the max number of bonded validators and the default status is bonded.

closes: #4099

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• Wrote tests

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[codecov]

Codecov Report

Merging #4177 into develop will decrease coverage by <.01%.
The diff coverage is 51.61%.

@@             Coverage Diff             @@
##           develop    #4177      +/-   ##
===========================================
- Coverage    60.19%   60.18%   -0.01%     
===========================================
  Files          212      212              
  Lines        15167    15187      +20     
===========================================
+ Hits          9130     9141      +11     
- Misses        5412     5417       +5     
- Partials       625      629       +4

[fedekunze]

ACK. Side note, we should probably abstract the pagination functionality into a util to reuse it on other queriers as well.

[rigelrozanski]

looks good

Has this been tested on the CLI? There are no new cli flags in this PR (gaiacli query staking validators)

[alexanderbez]

Thanks for the review @rigelrozanski -- I addressed all your comments. With regards to the CLI, that was left untouched because the CLI and REST never implemented the same functionality really (ie. the CLI just returns all validators always). Should we change this too?