Fix. heading in hacktoberfest homepage

Author: Ankitchaudharyy

app/views/topics/show.html.slim

@@ -8,7 +8,7 @@
 hr.section-break
 
 .repos-list-wrapper
-  h2.repos-list-title All repos with with label #{@topic}.
+  h2.repos-list-title All repos with label #{@topic}.
 
   section.repo-list-with-pagination
     = render "pages/repos_with_pagination", repos: @repos