Merge Google Drive and Google Docs credentials

• Type: Task
• Status: Closed
• Priority: Minor
• Resolution: Completed
• Affects Version/s: None
• Fix Version/s: Master
• Component/s: Documents & Media
• Labels:
  • Apr_'19
  • pt-app-security-review
  • pt-upgrade-review
• Sprint: Col | Sprint 12 | Apr1 - Apr5
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/70905

At the moment we have 2 separate configurations for google drive credentials, one for document-library-opener-google-drive and another for document-library-google-docs.

Since both settings serve the same purpose, they should be merged so that users only have to set them in one place.