fix description line endings in typescript enums

[calebstott]

pymavlink/generator/mavgen_typescript.py

Line 37 in ac64ac0

"\t{} = {}, // {}\n".format(entry.name, entry.value, entry.description.rstrip("\r").rstrip("\n")))

If a xml schema contains a multiline description on windows, the CRLF remains in the generated code leaving a syntax error
I believe this is due to the order of the rstrip operations
Think it would be better to replace with a space, so then comments will still have some sort of separator