company-FIX external event subscription

Number of APIs: 2

1. externalEventSubscription GET {{url}}/{{environment}}/api/v2.0/companies({{companyId}})/externaleventsubscriptions?tenant={{tenant}}

2. externalEventSubscription Copy POST {{url}}/{{environment}}/api/v2.0/companies({{companyId}})/externaleventsubscriptions?tenant={{tenant}}