Use rules_elixir for rabbitmqctl (backport #11456) (backport #11485)

[mergify]

Make use of rules_elixir, which externalized portions of the elixir related bazel code in this repository, and compiles rabbitmqctl and runs its tests without mix. Consequently, it is more efficient, and should be a bit more reliable.

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This is an automatic backport of pull request #11456 done by Mergify.

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This is an automatic backport of pull request #11485 done by Mergify.

[mergify]

Cherry-pick of 7f585d4 has failed:

On branch mergify/bp/v3.12.x/pr-11485
Your branch is up to date with 'origin/v3.12.x'.

You are currently cherry-picking commit 7f585d4102.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   .bazelrc
	modified:   BUILD.bazel
	modified:   MODULE.bazel
	modified:   bazel/BUILD.ranch
	modified:   bazel/bzlmod/extensions.bzl
	modified:   bazel/elixir/BUILD.bazel
	deleted:    bazel/elixir/elixir.bzl
	deleted:    bazel/elixir/elixir_as_app.bzl
	deleted:    bazel/elixir/elixir_build.bzl
	new file:   bazel/elixir/elixir_bytecode.bzl
	new file:   bazel/elixir/elixir_escript_main.bzl
	new file:   bazel/elixir/elixir_escript_main.exs
	deleted:    bazel/elixir/elixir_toolchain.bzl
	deleted:    bazel/elixir/iex_eval.bzl
	modified:   bazel/elixir/mix_archive_build.bzl
	deleted:    bazel/repositories/BUILD.bazel
	deleted:    bazel/repositories/BUILD_external.tpl
	deleted:    bazel/repositories/BUILD_internal.tpl
	deleted:    bazel/repositories/defaults.bzl.tpl
	deleted:    bazel/repositories/elixir_config.bzl
	modified:   deps/rabbit/BUILD.bazel
	modified:   deps/rabbitmq_auth_backend_oauth2/BUILD.bazel
	modified:   deps/rabbitmq_cli/rabbitmqctl.bzl
	deleted:    deps/rabbitmq_cli/rabbitmqctl_check_formatted.bzl
	deleted:    deps/rabbitmq_cli/rabbitmqctl_test.bzl
	modified:   deps/rabbitmq_cli/test/core/command_modules_test.exs
	renamed:    deps/rabbitmq_cli/test/json_formatting.exs -> deps/rabbitmq_cli/test/json_formatting_test.exs
	modified:   deps/rabbitmq_cli/test/test_helper.exs
	modified:   deps/rabbitmq_consistent_hash_exchange/BUILD.bazel
	modified:   deps/rabbitmq_ct_client_helpers/BUILD.bazel
	modified:   deps/rabbitmq_federation/BUILD.bazel
	modified:   deps/rabbitmq_federation_management/BUILD.bazel
	modified:   deps/rabbitmq_management/BUILD.bazel
	modified:   deps/rabbitmq_management_agent/BUILD.bazel
	modified:   deps/rabbitmq_mqtt/BUILD.bazel
	modified:   deps/rabbitmq_shovel/BUILD.bazel
	modified:   deps/rabbitmq_shovel_management/BUILD.bazel
	modified:   deps/rabbitmq_stomp/BUILD.bazel
	modified:   deps/rabbitmq_stream/BUILD.bazel
	modified:   deps/rabbitmq_stream_management/BUILD.bazel
	modified:   deps/rabbitmq_top/BUILD.bazel
	modified:   deps/rabbitmq_tracing/BUILD.bazel
	modified:   deps/rabbitmq_web_mqtt/BUILD.bazel
	modified:   deps/rabbitmq_web_stomp/BUILD.bazel
	modified:   rabbitmq.bzl
	modified:   rabbitmq_home.bzl

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   deps/rabbitmq_cli/BUILD.bazel
	both modified:   deps/rabbitmq_ct_helpers/BUILD.bazel

Cherry-pick of 1de9bb9 has failed:

On branch mergify/bp/v3.12.x/pr-11485
Your branch is ahead of 'origin/v3.12.x' by 5 commits.
  (use "git push" to publish your local commits)

You are currently cherry-picking commit 1de9bb9aab.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   MODULE.bazel

no changes added to commit (use "git add" and/or "git commit -a")

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally