php: Allow using `intelephense` from PATH (#14643)
This PR updates the PHP extension to use `intelephense` from the PATH,
if it exists.
Tested using the following Nix shell:
```sh
NIXPKGS_ALLOW_UNFREE=1 nix-shell -p php nodePackages_latest.intelephense
```
Resolves #11994.
Release Notes:
- N/A
40ed3b6977Marshall Bowers committed on 7/17/2024, 1:20:31 PM· committed by GitHubparentbd02f4f