chore: remove repetitive words (#10573)

Signed-off-by: careworry <worrycare@outlook.com>

Author: careworry

lib/syntax_suggest/clean_document.rb

@@ -267,7 +267,7 @@ def join_groups(groups)
       groups.each do |lines|
         line = lines.first
 
-        # Handle the case of multiple groups in a a row
+        # Handle the case of multiple groups in a row
         # if one is already replaced, move on
         next if @document[line.index].empty?