if an openai message has content and multicontent, fix it before passing it off to the api

openai.go

@@ -43,6 +43,16 @@ func (o openai) requestToOpenAIRequest(request Request) oai.ChatCompletionReques
 			}
 		}
 
+		// openai does not allow Content and MultiContent to be set at the same time, so we need to check
+		if len(m.MultiContent) > 0 && m.Content != "" {
+			m.MultiContent = append([]oai.ChatMessagePart{{
+				Type: "text",
+				Text: m.Content,
+			}}, m.MultiContent...)
+
+			m.Content = ""
+		}
+
 		res.Messages = append(res.Messages, m)
 	}