NixOS friendly build process - explicitly detect NixOS and guix
NixOS friendly build process - explicitly detect NixOS and guix

This patch may be removed if

  https://github.com/NixOS/nixpkgs/issues/142383

and a similar change to guix is actioned.

versatica/mediasoup,versatica/mediasoup,ibc/MediaSoup,ibc/MediaSoup,versatica/mediasoup,versatica/mediasoup,versatica/mediasoup,versatica/mediasoup,versatica/mediasoup,ibc/MediaSoup,versatica/mediasoup,versatica/mediasoup