Use gazelle for external erlang deps (#6935)

* Add gazelle for use with update-repos command

* Use explicit BUILD.app_name files for erlang app deps

This allows us to remove the duplicate definitions in
workspace_helpers.bzl

These files are generated with gazelle. For instance:
BUILD.ra is generated with `bazel run gazelle -- update-repos
--verbose --build_files_dir=bazel hex.pm/ra@2.4.6`

Running gazelle this way will modify the WORKSPACE file, as gazelle
does not yet support MODULE.bazel files. Such changes to the WORKSPACE
can be dropped, and should not be committed. It may also update the
`moduleindex.yaml` file. Changes to `moduleindex.yaml` should be
committed.

However
* skip the explicit bazel/BUILD.osiris file, as osiris already contains the file in its repo
* skip the explict BUILD.inet_tcp_proxy_dist file, since the repo already contains a bazel BUILD.bazel file
  gazelle command: `bazel run gazelle -- update-repos --verbose --build_files_dir=bazel
inet_tcp_proxy_dist=github.com/rabbitmq/inet_tcp_proxy@master`
* jose is imported with `bazel run gazelle -- update-repos --verbose --build_files_dir=bazel
jose=github.com/michaelklishin/erlang-jose@d63c1c5c8f9c1a4f1438e234b886de8607a0034e`

* Move the bats dep directly to WORKSPACE, drop workspace_helpers.bzl

* Use bzlmod in windows tests

.github/workflows/test-windows.yaml

@@ -60,7 +60,6 @@ jobs:
       run: |
         bazelisk test //... ^
           --config=buildbuddy ^
-          --noexperimental_enable_bzlmod ^
           --test_tag_filters=-aws,-docker,-bats,-starts-background-broker ^
           --build_tests_only ^
           --verbose_failures

BAZEL.md

@@ -59,6 +59,17 @@ Note: This takes quite some time on a single machine.
 
 `bazel test //deps/rabbit:lazy_queue_SUITE`
 
+## Add/update an external dependency from hex.pm
+
+1. `bazel run gazelle -- update-repos --verbose --build_files_dir=bazel hex.pm/accept@0.3.5` to generate/update `bazel/BUILD.accept`
+  ~~`bazel run gazelle-update-repos -- -args hex.pm/accept@0.3.5`~~
+1. `git checkout WORKSPACE` to reset the workspace file
+1. Add/update the entry in MODULE.bazel
+
+## Add/update an external dependency from github
+
+`bazel run gazelle -- update-repos --verbose --build_files_dir=bazel github.com/extend/ct_helper`
+
 ## Additional Useful Commands
 
 - Format all bazel files consistently (requires [buildifier](https://github.com/bazelbuild/buildtools/blob/master/buildifier/README.md)):

BUILD.bazel

@@ -7,6 +7,8 @@ load("@rules_pkg//:pkg.bzl", "pkg_tar")
 load("@rules_erlang//:dialyze.bzl", "plt")
 load("@rules_erlang//:shell.bzl", "shell")
 load("@rules_erlang//:erl_eval.bzl", "erl_eval")
+load("@bazel_gazelle//:def.bzl", "gazelle")
+load("@rules_erlang//gazelle:def.bzl", "GAZELLE_ERLANG_RUNTIME_DEPS")
 load("//bazel/elixir:iex_eval.bzl", "iex_eval")
 load(":rabbitmq_home.bzl", "rabbitmq_home")
 load(":rabbitmq_run.bzl", "rabbitmq_run", "rabbitmq_run_command")
@@ -20,6 +22,25 @@ exports_files([
     "release-notes",
 ])
 
+# gazelle:prefix github.com/rabbitmq/rabbitmq-server
+
+gazelle(
+    name = "gazelle",
+    data = GAZELLE_ERLANG_RUNTIME_DEPS,
+    gazelle = "@rules_erlang//gazelle:gazelle_erlang_binary",
+)
+
+# gazelle(
+#     name = "gazelle-update-repos",
+#     extra_args = [
+#         "--verbose",
+#         "--build_files_dir=bazel",
+#     ],
+#     command = "update-repos",
+#     data = GAZELLE_ERLANG_RUNTIME_DEPS,
+#     gazelle = "@rules_erlang//gazelle:gazelle_erlang_binary",
+# )
+
 bool_flag(
     name = "enable_test_build",
     build_setting_default = False,