Issue #209 Fix Internal server error in Dashboard

[oss-aimoto]

Analysis

The cause is that the argument userName of the searchIdentities method is in DN format(id=demo,ou=user,dc=openam,dc=osstech,dc=co,dc=jp）

Solution

The argument of searchIdentities method is the user name(such as "demo").

Testing

Internal Server Error does't appear in Dashboard

Regression testing

• FIDO2 (WebAuthn) Authentication Devices is displayed
• FIDO2 (WebAuthn) Authentication Devices can be deleted

[tsujiguchitky]

The modified code uses ContextHelper to get the user id. This way is the same as UserDevicesResource.

[tsujiguchitky]

LGTM