Drop `username` requirement from documentation

The `username` setting is no longer used as documented in the
`upgrade.md` already. So we drop it here as well.

Change-Id: I7d04901472d89885d10932a9bffdbabdb7ea0bad
diff --git a/src/main/resources/Documentation/config-connectivity.md b/src/main/resources/Documentation/config-connectivity.md
index daa947a..92b0c36 100644
--- a/src/main/resources/Documentation/config-connectivity.md
+++ b/src/main/resources/Documentation/config-connectivity.md
@@ -2,7 +2,7 @@
 ========================
 
 In order for @PLUGIN@ to connect to your Phabricator instance, url (without
-trailing “/api”, “/conduit” or some such), user, and certificate are required in
+trailing “/api”, “/conduit” or some such), and certificate are required in
 your site's `etc/gerrit.config` or `etc/secure.config` under the `@PLUGIN@`
 section.