Feature: Support account linking with actions
Description: Description: Currently auth0 actions are not supporting account linking, leaving us basically with 2 options:
a) to use account linking extension (Account Link Extension) that depends on deprecated feature - rules
b) develop separate flow (user-initiated) for account linking after user is logged in with not-linked account
Use-case: Assume we are providing our users with multiple login options (email/social). We want to prevent duplicated accounts, the experience should be seamless (without unnecessary redirects required in a workaround - user-initiated flow) and well supported (cannot use features that will be deprecated in following months).