Vscode extension updates

[kinnison]

Motivation for this change

As we approach the final release of 21.05 it would be good to keep vscode extensions as up-to-date as we can. Especially the live-share extension whose compatibility might depend on being up-to-date between systems. This change updates the live-share extension and further updates the python extension relative to the last PR I submitted.

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
  • ms-python.python: 692M -> 681M
  • ms-vsliveshare-vsliveshare: 752M -> 752M
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

cc @lukegb

[r-rmcgibbo]

Result of nixpkgs-review pr 122913 at d91ae6a run on x86_64-linux 1

2 packages built successfully:

• vscode-extensions.ms-python.python
• vscode-extensions.ms-vsliveshare.vsliveshare

[deviant]

I think you missed #122731