fix: JSON.fast_generate is deprecated

thanks @sferik!

Author: ms-jpq

lib/openai/internal/util.rb

@@ -570,9 +570,9 @@ def encode_content(headers, body)
           content_type = headers["content-type"]
           case [content_type, body]
           in [OpenAI::Internal::Util::JSON_CONTENT, Hash | Array | -> { primitive?(_1) }]
-            [headers, JSON.fast_generate(body)]
+            [headers, JSON.generate(body)]
           in [OpenAI::Internal::Util::JSONL_CONTENT, Enumerable] unless body.is_a?(OpenAI::Internal::Type::FileInput)
-            [headers, body.lazy.map { JSON.fast_generate(_1) }]
+            [headers, body.lazy.map { JSON.generate(_1) }]
           in [%r{^multipart/form-data}, Hash | OpenAI::Internal::Type::FileInput]
             boundary, strio = encode_multipart_streaming(body)
             headers = {**headers, "content-type" => "#{content_type}; boundary=#{boundary}"}

test/openai/client_test.rb

@@ -327,4 +327,4 @@ def test_default_headers
       headers.each { refute_empty(_1) }
     end
   end
-end
+end