- Support fnm when detecting node binary (#32890)

Summary:
Since 0.64, local code in `Bundle React Native code and images` step for iOS is not enough anymore.
This add support for [fnm](https://github.com/Schniz/fnm) that is widely used this days.

## Changelog

<!-- Help reviewers and the release process by writing your own changelog entry. For an example, see:
https://github.com/facebook/react-native/wiki/Changelog
-->

[General] [Added] - Support fnm when detecting node binary

Pull Request resolved: #32890

Test Plan: I use fnm & it's working. Tested this code via patch-package.

Reviewed By: christophpurrer

Differential Revision: D33766842

Pulled By: cortinico

fbshipit-source-id: 77bbda2c7742de9ec64e6faa9a3526d3997bb4aa

Author: MoOx

scripts/find-node.sh

@@ -60,3 +60,10 @@ if [[ -x "$HOME/.volta/bin/node" ]]; then
   export VOLTA_HOME="$HOME/.volta"
   export PATH="$VOLTA_HOME/bin:$PATH"
 fi
+
+# Set up the fnm node version manager if present
+if [[ -x "$HOME/.fnm/fnm" ]]; then
+  eval "$("$HOME/.fnm/fnm" env)"
+elif [[ -x "$(command -v brew)" && -x "$(brew --prefix fnm)/bin/fnm" ]]; then
+  eval "$("$(brew --prefix fnm)/bin/fnm" env)"
+fi