Bump httparty from 0.18.0 to 0.21.0#9

dependabot[bot] wants to merge 1 commit intomastericostan/bitmex-api-ruby:masterfrom

dependabot/bundler/httparty-0.21.0icostan/bitmex-api-ruby:dependabot/bundler/httparty-0.21.0Copy head branch name to clipboard