As discovered in:
https://github.com/status-im/status-mobile/pull/15225
The attempt to fix this in:
https://github.com/status-im/status-mobile/pull/15180
But it doesn't appear to work, so instead I'm allowing an override of
`NODE_BINARY` variable and spetting it when defining the Nix shell.
The key things here are:
* Xcode injects its own paths into `PATH` which breaks Nix env.
* Combining Nix shells with `inputsFrom` does not inherit all vars.
It's important to set these variables in `shellHook` and not elsewhere.
Signed-off-by: Jakub Sokołowski <jakub@status.im>