[CI} fix pkgs.python in shell.nix]

2 jobs for 339-dev-docs-download in 23 minutes and 30 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #2814
deps

00:12:58

failed #2815
test

00:10:32

 
Name Stage Failure
failed
test Test
    Make sure the source file exists, and that it has been provided as an input to the compiler.


See https://github.com/purescript/documentation/blob/master/errors/ModuleNotFound.md for more information,
or to contribute content related to this error.


Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1