Motivation for this change

New release: https://github.com/ethereum/go-ethereum/releases/tag/v1.9.24

This is security critical, although we seem to be building with go 1.15.5 on master, so the update is not strictly needed here.

This should be backported, but I'm not sure how to go about it. Afaict go 1.15 is currently only available on master?

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)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.