remove :MB which was for fcitx4

Author: lilydjwg

vimrc

@@ -817,7 +817,6 @@ command -nargs=+ Reindent call Lilydjwg_reindent(<f-args>)
 command -range=% ClsXML <line1>,<line2>!tidy -utf8 -iq -xml
 command -range=% ClsHTML <line1>,<line2>!tidy -utf8 -iq -omit -w 0
 command -range=% ClsJSON setf json | <line1>,<line2>!jq .
-command MB tabe ~/temp/mb
 command -nargs=1 -complete=customlist,Lilydjwg_complete_So So runtime so/<args>.vim
 command -nargs=1 Delmark delm <args>|wviminfo!
 "   删除空行