refactor: replace pricing api with @arkecosystem/platform-sdk

[faustbrian]

Replaces the pricing APIs with ones from https://github.com/ArkEcosystem/platform-sdk which will be used to share things across our applications. Also removes a bunch of methods that I couldn't find any reference of usage for.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (develop@dc46646). Click here to learn what that means.
The diff coverage is 51.42%.

@@            Coverage Diff             @@
##             develop    #1786   +/-   ##
==========================================
  Coverage           ?   59.42%           
==========================================
  Files              ?      363           
  Lines              ?     9025           
  Branches           ?     1831           
==========================================
  Hits               ?     5363           
  Misses             ?     3480           
  Partials           ?      182

Impacted Files	Coverage Δ
...rc/renderer/components/MarketChart/MarketChart.vue	31.85% <0%> (ø)
src/renderer/store/modules/market.js	4.34% <0%> (ø)
src/renderer/components/Network/NetworkModal.vue	47.9% <100%> (ø)
src/renderer/services/price-api.ts	53.12% <53.12%> (ø)

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