netlify-cli: fix build
netlify-cli: fix build

This commit uses the ESBUILD_BINARY_PATH env variable of esbuild to
supply a Nix managed esbuild binary. Otherwise the postInstall script
would try to make a network request.

See below links for more info:

https://github.com/evanw/esbuild/pull/597/files
https://docs.netlify.com/configure-builds/file-based-configuration/#functions

NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs