DRILL-8056: Add OAuth2 Support for HTTP Rest Plugin (#2401)
* DRILL-8056: Add OAuth2 Support for HTTP Rest Plugin
* Fixed one unit test and removed code from other branch
* Fix UT
* WIP
* Moving to Cred provider
* WIP
* UT working with Cred provider
* Successfully optained tokens
* Ready for review
* Fixed Checkstyle
* Code cleanup
* Updated docs and minor code cleanup
* Moved okhttp3 to test scope
* Fixed pom... again
* Pom fixes
* Added redirect URI to access token request
* Added token type to config
* Doc update
* Updated docs and addressed review comments
* Initial work with persistent store
* 2/3 Unit tests passing
* All unit tests passing
* Code cleanup
* Passing manual tests with Clickup and Salesforce
* Final revisions
* Fix resource leak
* Added Success FTL
* Fix resource leak
* UTs passing
* Addressed Review Comments
* Removed unused import
