Bump google-protobuf from 3.25.1 to 3.25.5 in /docs (#791)

Bumps [google-protobuf](https://github.com/protocolbuffers/protobuf)
from 3.25.1 to 3.25.5.

Author: dependabot[bot]

docs/Gemfile.lock

@@ -11,8 +11,8 @@ GEM
     eventmachine (1.2.7)
     ffi (1.16.3)
     forwardable-extended (2.6.0)
-    google-protobuf (3.25.1)
-    google-protobuf (3.25.1-x86_64-darwin)
+    google-protobuf (3.25.5)
+    google-protobuf (3.25.5-x86_64-darwin)
     http_parser.rb (0.8.0)
     i18n (1.14.1)
       concurrent-ruby (~> 1.0)