Update csproj with removed file reference.

Author: acoumb

src/Umbraco.Cms.Integrations.Commerce.Shopify/Umbraco.Cms.Integrations.Commerce.Shopify.csproj

@@ -254,7 +254,6 @@
     <Compile Include="Editors\ShopifyProductPickerConfiguration.cs" />
     <Compile Include="Editors\ShopifyProductPickerConfigurationEditor.cs" />
     <Compile Include="Editors\ShopifyProductPickerPropertyEditor.cs" />
-    <Compile Include="Services\IShopifyService.cs" />
     <Compile Include="Services\SettingsService.cs" />
     <Compile Include="Services\ShopifyService.cs" />
     <Compile Include="ShopifyComposer.cs" />