Webmock: Stubbing a post request with a body and making a matching request errors

require "webmock"
require "httpx"
require "httpx/adapters/webmock"

include WebMock::API
WebMock.enable!

stub_request(:post, "https://example.com/api/v1/access_token")
  .with(body: { grant_type: "client_credentials" })

response = HTTPX.post("https://example.com/api/v1/access_token",
  form: { grant_type: "client_credentials" },
)

/home/user/.rbenv/versions/3.3.5/lib/ruby/3.3.0/delegate.rb:91:in `method_missing': undefined method `split' for an instance of #<Class:0x00007f9a4a1e8840> (NoMethodError)
        from /home/user/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/gems/webmock-3.24.0/lib/webmock/util/query_mapper.rb:75:in `collect_query_parts'
        from /home/user/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/gems/webmock-3.24.0/lib/webmock/util/query_mapper.rb:56:in `query_to_values'
        from /home/user/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/gems/webmock-3.24.0/lib/webmock/request_pattern.rb:313:in `body_as_hash'
        from /home/user/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/gems/webmock-3.24.0/lib/webmock/request_pattern.rb:288:in `matches?'
        from /home/user/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/gems/webmock-3.24.0/lib/webmock/request_pattern.rb:40:in `matches?'
        from /home/user/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/gems/webmock-3.24.0/lib/webmock/stub_registry.rb:75:in `block in request_stub_for'
        from /home/user/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/gems/webmock-3.24.0/lib/webmock/stub_registry.rb:74:in `each'
        from /home/user/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/gems/webmock-3.24.0/lib/webmock/stub_registry.rb:74:in `detect'
        from /home/user/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/gems/webmock-3.24.0/lib/webmock/stub_registry.rb:74:in `request_stub_for'
        from /home/user/.rbenv/versions/3.3.5/lib/ruby/gems/3.3.0/gems/webmock-3.24.0/lib/webmock/stub_registry.rb:66:in `response_for_request'
        from /home/user/code/httpx/lib/httpx/adapters/webmock.rb:107:in `send'
        from /home/user/code/httpx/lib/httpx/session.rb:132:in `block in send_request'
        from /home/user/code/httpx/lib/httpx/session.rb:130:in `catch'
        from /home/user/code/httpx/lib/httpx/session.rb:130:in `send_request'
        from /home/user/code/httpx/lib/httpx/session.rb:254:in `block in _send_requests'
        from /home/user/code/httpx/lib/httpx/session.rb:253:in `each'
        from /home/user/code/httpx/lib/httpx/session.rb:253:in `_send_requests'
        from /home/user/code/httpx/lib/httpx/session.rb:245:in `send_requests'
        from /home/user/code/httpx/lib/httpx/session.rb:72:in `request'
        from /home/user/code/httpx/lib/httpx/chainable.rb:17:in `request'
        from /home/user/code/httpx/lib/httpx/chainable.rb:10:in `post'
        from test.rb:12:in `<main>'

I believe this is caused by !351 (merged) and previously worked.