nix-copy-closure: Drop Nix <= 1.7 compat
nix-copy-closure: Drop Nix <= 1.7 compat

dezgeg/nix,layus/nix,bennofs/nix,shlevy/nix,zimbatm/nix,bennofs/nix,rycee/nix,peti/nix,NixOS/nix,ysangkok/nix,peti/nix,rycee/nix,NixOS/nix,layus/nix,pikajude/nix,ehmry/nix,NixOS/nix,zimbatm/nix,pikajude/nix,ehmry/nix,ehmry/nix,NixOS/nix,shlevy/nix,dezgeg/nix,ehmry/nix,layus/nix,rycee/nix,dtzWill/nix,bennofs/nix,vcunat/nix,dezgeg/nix,pikajude/nix,vcunat/nix,bennofs/nix,ysangkok/nix,ehmry/nix,shlevy/nix,rycee/nix,ysangkok/nix,dtzWill/nix,dtzWill/nix,shlevy/nix,peti/nix,dtzWill/nix,dezgeg/nix,rycee/nix,ehmry/nix,dtzWill/nix,zimbatm/nix,peti/nix,vcunat/nix,peti/nix,zimbatm/nix,layus/nix,vcunat/nix,NixOS/nix,dezgeg/nix,shlevy/nix,layus/nix