Enhancement: Add prompt parameter to OIDC flow

Added prompt parameter to the authorization request in case OIDC is supported.
By default, select_account will be sent. It can be changed via branding or MDM.

https://github.com/owncloud/android/pull/4011
https://github.com/owncloud/android/issues/3862
https://github.com/owncloud/android/issues/3984
