add create sell and buy crypto order mutations

spec/graphql/inputs/create_buy_crypto_order_attributes_input_spec.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+describe Inputs::CreateBuyCryptoOrderAttributesInput do
+  subject { described_class }
+
+  describe "fields" do
+    it { is_expected.to(accept_argument("currency_id").of_type("ID!")) }
+    it { is_expected.to(accept_argument("amount_cents").of_type("Int!")) }
+  end
+end

spec/graphql/inputs/create_sell_crypto_order_attributes_input_spec.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+describe Inputs::CreateSellCryptoOrderAttributesInput do
+  subject { described_class }
+
+  describe "fields" do
+    it { is_expected.to(accept_argument("currency_id").of_type("ID!")) }
+    it { is_expected.to(accept_argument("amount").of_type("String!")) }
+  end
+end