Draft: Use Vite for e2e specs

What does this MR do and why?

Implements #521669.

This MR re-enables Vite after !177205 (merged), which was caused by #454520 (closed).

This is the last step before we can default to Vite in GDK. Vite has undergone a huge refinement over the last 3 months, so it should be much more stable running specs in CI.

Eventually we'll switch to assets compilation using Vite inside gdk:compile-test-assets and use assets without Vite dev server.