title: Link a third party application account in Cognito
body: <p>I need to link a third party application credentials to the one the user uses to connect to my application through Cognito. In other words: user connects to application A (my application), then application A asks user for credentials to connect to application B. Application A then interact with application B with the credentials provided by the user. I would like to link those identities but let the user connect to application A only with credentials I provided him (and not from the ones he uses for B).</p>
  <p>AWS has AdminLinkProviderForUser in Cognito which doesn't satisfy the last requirement.</p>
  <p>Application B offers multiple authentications: Form, Basic HTTP, SSO, OAuth2 and OpenID.</p>
  <p>Is there any way to link the two identities in the way described above and store it in Cognito for future use?</p>