fix a typo

Author: teranex

ftplugin/vimwiki.vim

@@ -12,5 +12,5 @@ if vimwiki_tasks#config('taskwarrior_integration', 1)
     command! CopyTaskID call vimwiki_tasks#display_task_id(1)
     command! DisplayTaskUUID call vimwiki_tasks#display_task_uuid(0)
     command! CopyTaskUUID call vimwiki_tasks#display_task_uuid(1)
-    command! -nargs=1 -bang InsertTasks cal vimwiki_tasks#insert_tasks(<q-args>, '<bang>')
+    command! -nargs=1 -bang InsertTasks call vimwiki_tasks#insert_tasks(<q-args>, '<bang>')
 endif