Remove extra parenthesis (minor)

Author: cnotin

articles/active-directory/external-identities/authentication-conditional-access.md

@@ -46,7 +46,7 @@ When an Azure AD organization shares resources with external users with an ident
 
 The following diagram illustrates the authentication flow when an external user signs in with an account from a non-Azure AD identity provider, such as Google, Facebook, or a federated SAML/WS-Fed identity provider.
 
-[ ![Diagram showing the Authentication flow for B2B guest users from an external directory.](media/authentication-conditional-access/authentication-flow-b2b-guests.png) ](media/authentication-conditional-access/authentication-flow-b2b-guests.png#lightbox))
+[ ![Diagram showing the Authentication flow for B2B guest users from an external directory.](media/authentication-conditional-access/authentication-flow-b2b-guests.png) ](media/authentication-conditional-access/authentication-flow-b2b-guests.png#lightbox)
 
 | Step | Description |
 |--------------|-----------------------|