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#### Describe the bug
Some servers are not sending a zlib header in their deflated data. CURL had the same problem and implemented a "fix" for it: https://github.com/curl/curl/blob/5c932f8fe9dad94a7417702958ffa9e8db67c549/lib/content_encoding.c#L227-L229

Axios is also returning a `Z_DATA_ERROR` in this case.

#### To Reproduce

Use axios to request a page without a zlib header in the deflated data (e.g. https://www.konicaminolta.eu/eu-en/about-us/corporate-book) and force it to only accept deflate encoding.

```js
let url = 'https://www.konicaminolta.eu/eu-en/about-us/corporate-book';
let config = {
  headers: { 'Accept-Encoding': 'deflate' }
};

await axios.get(url, config);
```

#### Expected behavior

Getting the correctly inflated data.

#### Environment
 - Axios Version [0.21.1]


#### Additional context/Screenshots


test/unit/adapters/http.js
const {handler, useBuffering = false, rate = undefined, port = 4444} = typeof options === 'function' ? {
    handler: options
  } : options || {};
  return new Promise((resolve, reject) => {
    http.createServer(handler || async function (req, res) {
      try {
        req.headers['content-length'] && res.setHeader('content-length', req.headers['content-length']);
        var dataStream = req;
        if (useBuffering) {
          dataStream = stream.Readable.from(await getStream(req));
        }
        var streams = [dataStream];
        if (rate) {
          streams.push(new Throttle({rate}))
        }
        streams.push(res);
        stream.pipeline(streams, (err) => {
          err && console.log('Server warning: ' + err.message)
        });
      } catch (err){
        console.warn('HTTP server error:', err);
      }
    }).listen(port, function (err) {
      err ? reject(err) : resolve(this);
    });
  });
}
function generateReadableStream(length = 1024 * 1024, chunkSize = 10 * 1024, sleep = 50) {