remove useless line

Author: JulienVerbrugge

content/extensions/ui-extensions.md

@@ -381,7 +381,6 @@ The JWT token consists of three main parts: the header, the body (payload), and
 * ```exp``` The expiration time of the token.
 * ```userId``` The PIM user identifier (in this case, ```1```).
 
-
 *A signature*
 
 * The signature is used to verify that the token is valid and has not been tampered with. It is generated by combining the encoded header and payload, and then signing them with the secret key. The resulting signature might look like: