Create a new asset upload session.

Create a new asset upload session for the AdAccount. A URL would be returned in a successful response for uploading the actual asset content.
After asset upload has been successfully completed, see the campaign creation guide and follow the instructions outlined in Section 4-1. Upload a creative asset to storage to initiate a resumable upload session for uploading the creative asset to Google Cloud Storage.
For v1.7 or later, follow Section 4-1 for those using Moloco Ads API v1.7 or later.