Fix __init__.py

Author: jhgoebbert

jupyter_xprahtml5_proxy/__init__.py

@@ -120,7 +120,7 @@ def _get_random_alphanumeric_string(length):
         '--tcp-encryption=AES',
         '--tcp-encryption-keyfile=' + fpath_aeskey,
         '--clipboard-direction=both',
-        '--keyboard-sync=no',  # prevent keys from repeating unexpectedly on high latency
+        '--no-keyboard-sync',  # prevent keys from repeating unexpectedly on high latency
         '--no-mdns',  # do not advertise the xpra session on the local network
         '--no-bell',
         '--no-speaker',