chore: update protobuf to 23.1 (#200)

This PR updates protobuf to version 23.1.

It's a lesser version than the update in #187, but 23.1 has the virtue
of already [being present in
BCR](https://github.com/bazelbuild/bazel-central-registry/tree/main/modules/protobuf/23.1).

Fixes #178
diff --git a/MODULE.bazel b/MODULE.bazel
index 03f25ac..618f9ac 100644
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -15,5 +15,5 @@
 bazel_dep(name = "stardoc", version = "0.5.6", dev_dependency = True, repo_name = "io_bazel_stardoc")
 bazel_dep(name = "rules_cc", version = "0.0.1", dev_dependency = True)
 bazel_dep(name = "googletest", version = "1.11.0", dev_dependency = True, repo_name = "com_google_googletest")
-bazel_dep(name = "protobuf", version = "21.7", dev_dependency = True, repo_name = "com_google_protobuf")
+bazel_dep(name = "protobuf", version = "23.1", dev_dependency = True, repo_name = "com_google_protobuf")
 bazel_dep(name = "platforms", version = "0.0.8", dev_dependency = True)
diff --git a/dev_deps.bzl b/dev_deps.bzl
index efbafb9..a9fb212 100644
--- a/dev_deps.bzl
+++ b/dev_deps.bzl
@@ -58,10 +58,10 @@
 
     http_archive(
         name = "com_google_protobuf",
-        sha256 = "75be42bd736f4df6d702a0e4e4d30de9ee40eac024c4b845d17ae4cc831fe4ae",
-        strip_prefix = "protobuf-21.7",
+        sha256 = "dc167b7d23ec0d6e4a3d4eae1798de6c8d162e69fa136d39753aaeb7a6e1289d",
+        strip_prefix = "protobuf-23.1",
         urls = [
-            "https://mirror.bazel.build/github.com/protocolbuffers/protobuf/archive/v21.7.tar.gz",
-            "https://github.com/protocolbuffers/protobuf/archive/v21.7.tar.gz",
+            "https://mirror.bazel.build/github.com/protocolbuffers/protobuf/archive/v23.1.tar.gz",
+            "https://github.com/protocolbuffers/protobuf/archive/v23.1.tar.gz",
         ],
     )