Added role check

This release adds hasRealmRole and hasResourceRole, which calls the $keycloak object.

Updated Keycloak version

Updated the keycloak javascript adapter version to 4.8.3, aligned with RedHat SSO 7.3.

Better handling of expired refresh token

If updateToken fails (on failure to refresh token or the session has expired), call keycloak.clearToken().

This avoids futile attempts to refresh a token, and a lot of ERROR logs on the Keycloak server.

Added support for yarn

Support for yarn was removed by a mistake, this release fixes that.