This corrects the multi-node test after a couple recent changes which
resulted in it being broken.
The `lib.toString` change was an incorrect tree-wide refactor, and the
aarch64 change also introduced an error in python indentation/formatting
I believe.
*Flags implies a list
slightly relevant:
> stdenv: start deprecating non-list configureFlags https://github.com/NixOS/nixpkgs/pull/173172
the makeInstalledTests function in `nixos/tests/installed-tests/default.nix` isn't available outside of nixpkgs so
it's not a breaking change
- Replace misleading docs.
- Add new assertions to let configurations make more sense.
- Add clusterInit flag.
- Add some more docs about HA and non-HA modes setup.
- Improve multi-node tests for HA mode.
Fix https://github.com/NixOS/nixpkgs/issues/182085
