chore: move sdkutil coin functions to the coin package

[robert-zaremba]

Description

skdutil should be as small as possible.

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[codecov-commenter]

Codecov Report

Merging #1780 (f5cac14) into main (f3125a6) will not change coverage.
The diff coverage is 100.00%.

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@@           Coverage Diff           @@
##             main    #1780   +/-   ##
=======================================
  Coverage   57.69%   57.69%           
=======================================
  Files          78       78           
  Lines        8022     8022           
=======================================
  Hits         4628     4628           
  Misses       3053     3053           
  Partials      341      341           

Impacted Files	Coverage Δ
x/leverage/keeper/keeper.go	69.27% <100.00%> (ø)
x/leverage/keeper/msg_server.go	79.06% <100.00%> (ø)

[gsk967]

Move mkCoin func to New into coin package and use this New func instead of mkCoin over the testing

func New(denom string, amount int64) sdk.Coin {
    return sdk.NewInt64Coin(denom,amount)
}

[robert-zaremba]

Move mkCoin func to New into coin package and use this New func instead of mkCoin over the testing

good idea

[robert-zaremba]

moved mkCoin to coin.New

[gsk967]

LGTM