Add "plus" verbiage back to login limits

There was some confusion with the "and" since it can be interpreted that
you can only try logging in twelve times per hour in total but actually
you get two attempts per minute and then twelve per hour on top of that.

Author: code-asher

docs/FAQ.md

@@ -391,7 +391,8 @@ machine with few limitations.
 
 ## Does code-server have any security login validation?
 
-code-server supports setting a single password and limits logins to two per minute and twelve per hour. 
+code-server supports setting a single password and limits logins to two per
+minute plus an additional twelve per hour.
 
 ## Are there community projects involving code-server?