fix(spell): please the spell check

apps/emqx_conf/i18n/emqx_conf_schema.conf

@@ -940,7 +940,7 @@ until the RPC connection is considered lost."""
 
   log_file_handlers {
     desc {
-      en: """file-based log handlers."""
+      en: """File-based log handlers."""
       zh: """输出到文件的日志处理进程列表"""
     }
     label {