### Describe the bug

https://github.com/developer-choi/axios-error-report

TypeError is occurred (in 1.6.6 version)

<img width="184" alt="image" src="https://github.com/axios/axios/assets/51902362/1f7f6e7f-8c8b-4ef7-9854-5c08f572d58b">

<img width="171" alt="image" src="https://github.com/axios/axios/assets/51902362/36042439-a071-485e-b696-9f2c01849759">

### To Reproduce

https://github.com/developer-choi/axios-error-report

### Code snippet

_No response_

### Expected behavior

_No response_

### Axios Version

1.6.6

### Adapter Version

_No response_

### Browser

CHROME

### Browser Version

120.0.6099.225

### Node.js Version

20.11.0

### OS

Window 11
lib/core/Axios.js
serialize: validators.function
        }, true);
      }
    }
    
    config.method = (config.method || this.defaults.method || 'get').toLowerCase();
    
    let contextHeaders = headers && utils.merge(
      headers.common,
      headers[config.method]
    );
    headers && utils.forEach(
      ['delete', 'get', 'head', 'post', 'put', 'patch', 'common'],
      (method) => {
        delete headers[method];
      }
    );
    config.headers = AxiosHeaders.concat(contextHeaders, headers);
    
    const requestInterceptorChain = [];
    let synchronousRequestInterceptors = true;
    this.interceptors.request.forEach(function unshiftRequestInterceptors(interceptor) {
      if (typeof interceptor.runWhen === 'function' && interceptor.runWhen(config) === false) {
        return;
      }
      synchronousRequestInterceptors = synchronousRequestInterceptors && interceptor.synchronous;
      requestInterceptorChain.unshift(interceptor.fulfilled, interceptor.rejected);
    });
    const responseInterceptorChain = [];
    this.interceptors.response.forEach(function pushResponseInterceptors(interceptor) {