[small nit]: gh repo link to docs is broken

[tfiers]

It's currently https://cjdoris.github.io/PythonCall.jl/stable, but that 404s.
Should now be https://juliapy.github.io/PythonCall.jl/stable/.

[KronosTheLate]

Came here to make this issue:

[cjdoris]

Fixed now, thanks!