Replace Redundant Bech32 PubKey Functions

[alexanderbez]

There is no need for a (Must)Bech32ify* and (Must)Get*KeyBech32 set of functions for each Bech32 prefix/type. Replace them with a single pair of flexible functions that accept a Bech32PubKeyType. To support new Bech32 prefixes, just add/use a new Bech32PubKeyType variable/const.

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[codecov]

Codecov Report

Merging #5495 into master will increase coverage by <.01%.
The diff coverage is 87.5%.

@@            Coverage Diff            @@
##           master   #5495      +/-   ##
=========================================
+ Coverage    54.5%   54.5%   +<.01%     
=========================================
  Files         313     313              
  Lines       18910   18880      -30     
=========================================
- Hits        10307   10291      -16     
+ Misses       7811    7805       -6     
+ Partials      792     784       -8

Impacted Files	Coverage Δ
client/keys/add.go	41.13% <0%> (ø)	⬆️
types/address.go	62.31% <100%> (+1.53%)	⬆️
x/auth/types/stdtx.go	61.53% <100%> (ø)	⬆️
x/auth/vesting/types/vesting_account.go	86.64% <100%> (ø)	⬆️
x/auth/types/account.go	84.44% <100%> (ø)	⬆️
x/staking/types/msg.go	55.55% <33.33%> (ø)	⬆️
crypto/keys/output.go	58.13% <50%> (ø)	⬆️
x/staking/client/cli/tx.go	11.83% <50%> (ø)	⬆️
x/staking/types/validator.go	63.77% <75%> (ø)	⬆️
x/mock/app.go	62.83% <0%> (-1.36%)	⬇️