fix(_service): quote word

Author: akinomyoga

bash_completion

@@ -1824,7 +1824,7 @@ _service()
         _comp_sysvdirs
         _comp_compgen -l -- -W '$(command sed -e "y/|/ /" \
             -ne "s/^.*\(U\|msg_u\)sage.*{\(.*\)}.*$/\2/p" \
-            ${sysvdirs[0]}/${prev##*/} 2>/dev/null) start stop'
+            "${sysvdirs[0]}/${prev##*/}" 2>/dev/null) start stop'
     fi
 } &&
     complete -F _service service