Update `//proto` rules to provide all required dependencies. (#868)

diff --git a/WORKSPACE.bazel b/WORKSPACE.bazel
index 203ab8f..b5b1276 100644
--- a/WORKSPACE.bazel
+++ b/WORKSPACE.bazel
@@ -8,6 +8,10 @@
 
 rust_proto_repositories()
 
+load("@rules_rust//proto:transitive_repositories.bzl", "rust_proto_transitive_repositories")
+
+rust_proto_transitive_repositories()
+
 load("@rules_rust//bindgen:repositories.bzl", "rust_bindgen_repositories")
 
 rust_bindgen_repositories()
@@ -85,4 +89,4 @@
 
 load("@docs//:docs_transitive_deps.bzl", docs_transitive_deps = "transitive_deps")
 
-docs_transitive_deps(is_top_level = True)
+docs_transitive_deps()