chore(deps): update dependency rules_proto to v6

Author: renovate[bot]

WORKSPACE

@@ -48,10 +48,10 @@ bazel_skylib_workspace()
 
 http_archive(
     name = "rules_proto",
-    sha256 = "dc3fb206a2cb3441b485eb1e423165b231235a1ea9b031b4433cf7bc1fa460dd",
-    strip_prefix = "rules_proto-5.3.0-21.7",
+    sha256 = "303e86e722a520f6f326a50b41cfc16b98fe6d1955ce46642a5b7a67c11c0f5d",
+    strip_prefix = "rules_proto-6.0.0",
     urls = [
-        "https://github.com/bazelbuild/rules_proto/archive/refs/tags/5.3.0-21.7.tar.gz",
+        "https://github.com/bazelbuild/rules_proto/archive/refs/tags/6.0.0.tar.gz",
     ],
 )