chore(release): 1.0.0-alpha.4 [skip ci]

# [1.0.0-alpha.4](https://git.gitlab.arm.com/bazel/rules_download/compare/v1.0.0-alpha.3...v1.0.0-alpha.4) (2023-12-13)

### Bug Fixes

* upgrade `rules_toolchain` ([92d070e6](https://git.gitlab.arm.com/bazel/rules_download/commit/92d070e632be505c0c16c77a5bfebd593acbd548))