add space between Chinese and English characters

zh_CN/chapter08/zstd.po

@@ -107,8 +107,8 @@ msgid ""
 "filename> file in <filename class=\"directory\">/usr/lib</filename> will "
 "need to be recreated:"
 msgstr ""
-"删除静态库，并将共享库移动到<filename class=\"directory\">/lib</filename>。另"
-"外，<filename class=\"extension\">.so</filename> 符号链接也要在<filename "
+"删除静态库，并将共享库移动到 <filename class=\"directory\">/lib</filename> 。另"
+"外，<filename class=\"extension\">.so</filename> 符号链接也要在 <filename "
 "class=\"directory\">/usr/lib</filename> 中重建："
 
 #. type: Content of: <sect1><sect2><screen>