chore: delete JS-version of Beatport importer script

[arsinclair]

Beatport importer script has been migrated to TypeScript with a new delivery URL.

The old JS script needs to be deprecated in 3 stages:

1. Update the @downloadurl and @updateURL to point to the new location and bump the version — ✔️
2. Give the script managers some time to auto-upgrade user scripts and replace the source code of the JS script with a warning that script is moved — ✔️
3. (in 3-6 months, May-August 2026) Delete the old JS script entirely.