Update README.md

Author: socheatsok78

README.md

@@ -13,7 +13,7 @@ NAME:
 GLOBAL OPTIONS:
    --addr value                The addr used by the unoserver api server (default: "0.0.0.0:2004")
    --unoserver-addr value      The unoserver addr used by the unoconvert (default: "127.0.0.1:2002") [$UNOSERVER_ADDR]
-   --unoconvert-bin value      Set the unoconvert executable path. (default: "unoconvert") [$UNOCONVERT_EXECUTABLE_PATH]
+   --unoconvert-bin value      Set the unoconvert executable path. (default: "unoconvert") [$UNOCONVERT_BIN]
    --unoconvert-timeout value  Set the unoconvert run timeout (default: 0s) [$UNOCONVERT_TIMEOUT]
    --help, -h                  show help
    --version, -v               print the version