Prost: transitive dependencies in the same package are duplicated (https://github.com/bazelbuild/rules_rust/issues/2185)

a.proto

syntax = "proto3";

import "external.proto";

package transitive_same_package;

message A {
    external.External foobar = 1;
}

b.proto

syntax = "proto3";

import "a.proto";

package transitive_same_package;

message B {
    A a = 1;
}

BUILD.bazel

load("@rules_proto//proto:defs.bzl", "proto_library")
load("//proto/prost:defs.bzl", "rust_prost_library")

proto_library(
    name = "external_proto",
    srcs = ["external.proto"],
    strip_import_prefix = "/proto/prost/private/tests/transitive_same_package",
)

rust_prost_library(
    name = "external_proto_rs",
    proto = ":external_proto",
)

proto_library(
    name = "a_proto",
    srcs = ["a.proto"],
    strip_import_prefix = "/proto/prost/private/tests/transitive_same_package",
    deps = [":external_proto"],
)

rust_prost_library(
    name = "a_proto_rs",
    proto = ":a_proto",
)

proto_library(
    name = "b_proto",
    srcs = ["b.proto"],
    strip_import_prefix = "/proto/prost/private/tests/transitive_same_package",
    deps = [":a_proto"],
)

rust_prost_library(
    name = "b_proto_rs",
    proto = ":b_proto",
)

proto_library(
    name = "c_proto",
    srcs = ["c.proto"],
    strip_import_prefix = "/proto/prost/private/tests/transitive_same_package",
    deps = [":b_proto"],
)

rust_prost_library(
    name = "c_proto_rs",
    proto = ":c_proto",
)

c.proto

syntax = "proto3";

import "b.proto";

package transitive_same_package;

message C {
    B b = 1;
}

external.proto

syntax = "proto3";

package external;

message External {
    string name = 1;
}