Fix httpclient git source in the lockfile

Followup to rails#50911

Not quite sure what happened here, the commit is still the latest.
I simply ran `bundle lock --update=httpclient`.

When running the railties tests:
```rb
.........../home/earlopain/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/bundler/gems/httpclient-d57cc6d5ffee/lib/httpclient/auth.rb:11: warning: mutex_m was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.4.0.
You can add mutex_m to your Gemfile or gemspec to silence this warning.
/home/earlopain/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/bundler/gems/httpclient-d57cc6d5ffee/lib/httpclient/auth.rb:11: warning: mutex_m was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.4.0.
You can add mutex_m to your Gemfile or gemspec to silence this warning.
/home/earlopain/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/bundler/gems/httpclient-d57cc6d5ffee/lib/httpclient/auth.rb:11: warning: mutex_m was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.4.0.
You can add mutex_m to your Gemfile or gemspec to silence this warning.
/home/earlopain/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/bundler/gems/httpclient-d57cc6d5ffee/lib/httpclient/auth.rb:11: warning: mutex_m was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.4.0.
You can add mutex_m to your Gemfile or gemspec to silence this warning.
/home/earlopain/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/bundler/gems/httpclient-d57cc6d5ffee/lib/httpclient/auth.rb:11: warning: mutex_m was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.4.0.
You can add mutex_m to your Gemfile or gemspec to silence this warning.
/home/earlopain/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/bundler/gems/httpclient-d57cc6d5ffee/lib/httpclient/auth.rb:11: warning: mutex_m was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.4.0.
You can add mutex_m to your Gemfile or gemspec to silence this warning.
/home/earlopain/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/bundler/gems/httpclient-d57cc6d5ffee/lib/httpclient/auth.rb:11: warning: mutex_m was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.4.0.
You can add mutex_m to your Gemfile or gemspec to silence this warning.
/home/earlopain/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/bundler/gems/httpclient-d57cc6d5ffee/lib/httpclient/auth.rb:11: warning: mutex_m was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.4.0.
You can add mutex_m to your Gemfile or gemspec to silence this warning.
./home/earlopain/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/bundler/gems/httpclient-d57cc6d5ffee/lib/httpclient/auth.rb:11: warning: mutex_m was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.4.0.
You can add mutex_m to your Gemfile or gemspec to silence this warning.
...
```

You get the idea. Not sure why strict warnings don't pick this up.

Author: Earlopain

Gemfile.lock

@@ -13,6 +13,8 @@ GIT
   branch: master
   specs:
     httpclient (2.8.3)
+      mutex_m
+      webrick
 
 GIT
   remote: https://github.com/rails/sdoc.git
@@ -376,6 +378,7 @@ GEM
     msgpack (1.7.2)
     multi_json (1.15.0)
     multipart-post (2.3.0)
+    mutex_m (0.2.0)
     mysql2 (0.5.6)
     net-http-persistent (4.0.2)
       connection_pool (~> 2.2)