#### Is your feature request related to a problem? Please describe.
This is an optimazition of code.

#### Describe the solution you'd like
The following line of code comes from https://github.com/axios/axios/blob/master/lib/adapters/http.js#L403:
```js
reject(!cancel || (cancel && cancel.type) ? new CanceledError() : cancel);
```
It can be optimized as follows:
```js
reject(!cancel || cancel.type ? new CanceledError() : cancel);
```

#### Describe alternatives you've considered
When the code is executed to `(cancel && cancel.type)`, it means `!cancel` is false, so `cancel` is true, we can get `cancel.type` directly.

#### Additional context
no more

lib/adapters/http.js
AxiosError.ERR_BAD_RESPONSE,
            config,
            lastRequest
          ));
        });
        stream.on('error', function handleStreamError(err) {
          if (req.aborted) return;
          reject(AxiosError.from(err, null, config, lastRequest));
        });
        stream.on('end', function handleStreamEnd() {
          try {
            var responseData = responseBuffer.length === 1 ? responseBuffer[0] : Buffer.concat(responseBuffer);
            if (config.responseType !== 'arraybuffer') {
              responseData = responseData.toString(config.responseEncoding);
              if (!config.responseEncoding || config.responseEncoding === 'utf8') {
                responseData = utils.stripBOM(responseData);
              }
            }
            response.data = responseData;
          } catch (err) {
            reject(AxiosError.from(err, null, config, response.request, response));
          }
          settle(resolve, reject, response);
        });
      }
    });
    
    req.on('error', function handleRequestError(err) {