[MID PRI][Good First Task] Stop augmenting PATH for irrelevant packages.

[jordwalke]

I previously commited a change that prevents irrelevant packages from populating any of the variables for install/bin/man etc. Currently, however, all of those packages still populate the PATH, which means that even packages that don't perform any builds still complicate the PATH. I believe this makes invoking binaries with that environment slower (but also harder to debug).

[jordwalke]

You can confirm by doing esy sh -c 'echo $PATH' when you have a dependency on lodash or some totally JS package.

[bbqbaron]

PR here since history doesn't track across repos.