Add rules_shell in advance of Protobuf 29.0+ update. (#37595)

`rules_shell` is new, and currently largely delegates back to the bazel
native `sh_binary`, `sh_library`, and `sh_test`.

Protobuf 29.0+ explicitly depends on it, though BCR[^1] suggests a lot
of other things do too, so we'll load it just before `rules_cc`.

[^1]: https://registry.bazel.build/modules/rules_shell/0.3.0

Risk Level: low
Testing: CI

Signed-off-by: Alejandro R. Sedeño <[email protected]>

bazel/repositories.bzl

@@ -124,6 +124,9 @@ def envoy_dependencies(skip_targets = []):
     if "envoy_build_config" not in native.existing_rules().keys():
         _default_envoy_build_config(name = "envoy_build_config")
 
+    # Setup Bazel shell rules
+    external_http_archive(name = "rules_shell")
+
     # Setup Bazel C++ rules
     external_http_archive("rules_cc")
 

bazel/repository_locations.bzl

@@ -1120,6 +1120,19 @@ REPOSITORY_LOCATIONS_SPEC = dict(
         license = "Apache-2.0",
         license_url = "https://github.com/bazelbuild/rules_pkg/blob/{version}/LICENSE",
     ),
+    rules_shell = dict(
+        project_name = "Shell script rules for Bazel",
+        project_desc = "Bazel rules for shell scripts",
+        project_url = "https://github.com/bazelbuild/rules_shell",
+        version = "0.3.0",
+        sha256 = "d8cd4a3a91fc1dc68d4c7d6b655f09def109f7186437e3f50a9b60ab436a0c53",
+        strip_prefix = "rules_shell-0.3.0",
+        urls = ["https://github.com/bazelbuild/rules_shell/releases/download/v0.3.0/rules_shell-v0.3.0.tar.gz"],
+        use_category = ["build"],
+        release_date = "2024-11-06",
+        license = "Apache-2.0",
+        license_url = "https://github.com/protocolbuffers/rules_shell/blob/{version}/LICENSE",
+    ),
     com_github_wamr = dict(
         project_name = "Webassembly Micro Runtime",
         project_desc = "A standalone runtime with a small footprint for WebAssembly",