Use tmp file for secure cookie

[danielfrg]

Updating https://github.com/jupyterhub/jupyter-rsession-proxy/pull/94 to master so we can get it merged.

This is needed to support multiple RStudio Sessions in the same machine.

The actual changes are very little there are other linting changes that happened automatically because of my VS Code setup, I can remove those if needed but hopefully its ok :D

The actual changes are:

def _get_cmd(port):
        ntf = tempfile.NamedTemporaryFile()
        cmd = [
            get_rstudio_executable("rserver"),
            "--auth-none=1",
            "--www-frame-origin=same",
            "--www-port=" + str(port),
            "--www-verify-user-agent=0",
            "--secure-cookie-key-file=" + ntf.name,
        ]

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[danielfrg]

I updated the branch to master. @ryanlovett would you be able to take a look at this?

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[ryanlovett]

Lgtm. Thanks for your patience @danielfrg !

[danielfrg]

Thanks for merging!