Bazelisk for riscv64

All in the title, will be happy to have a release artifact for riscv64....

FYI
```sh
# enable qemu support for docker to run riscv64 image on amd64 host
$ docker run --pull always --rm --privileged multiarch/qemu-user-static --reset -p yes
# debian do provide a riscv64 image
$ docker run --platform linux/riscv64 --rm --init -it debian:latest bash
root# uname -m
riscv64
root# apt update
root# apt search bazel
bazel-bootstrap/stable 4.2.3+ds-11 riscv64
Tool to automate software builds and tests
bazel-bootstrap-data/stable 4.2.3+ds-11 all
Tool to automate software builds and tests (data files)
bazel-bootstrap-source/stable 4.2.3+ds-11 all
Tool to automate software builds and tests (source code)
```

No files, tests, or release entry points are named. Start by tracing the repository’s existing release-artifact configuration for supported architectures, then verify the riscv64 artifact through the same release path; done means a usable riscv64 release artifact is produced.

Written by the indexing model from the issue text.