Redundant new line in signature help

[hanspinckaers]

Related issue: ray-x/lsp_signature.nvim#56

I'm testing out the native lsp-client inside neovim with compe.nvim and lsp_signature.nvim., I'm seeing an additional newline in the config (also in the resolve information/documentation). I tried removing the \n in _md_text and _md_python which works, but I think the python fencing goes wrong then? I see ``` in my documentation.

[pappasam]

@hanspinckaers ah yes, empty docstrings weren't handled correctly here. Thanks for raising, am fixing now!