linux: Fix missing licenses in binary causing panics (#14561)

Turns out that the existing CI step for Nightly did create the licenses
and they have been baked into X86 builds ever since, because our
builders are stateful.

On ARM machines, the licenses wouldn't exist in the binary because we
called `script/generate-licenses` too late in `scripts/bundle-linux`,
after the binary had been created.

This removes the duplication and generates the licenses once, before the
binary is created.

Fixes #14302.

Release Notes:

- Fixed "View Dependency Licenses" (or `zed: open licenses`) crashing on
Linux ARM machines.
([#14302](https://github.com/zed-industries/zed/issues/14302)