fix typo in icons section

doc/development/ux_guide/basics.md

@@ -33,7 +33,7 @@ This is the typeface used for code blocks and references to commits, branches, a
 
 ## Icons
 
-GitLab has a strong, unique personality. When you look at any screen, you should know immediately know that it is GitLab. 
+GitLab has a strong, unique personality. When you look at any screen, you should know immediately that it is GitLab. 
 Iconography is a powerful visual cue to the user and is a great way for us to reflect our particular sense of style.
 
 - **Standard size:** 16px * 16px