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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


lib/adapters/http.js
onDownloadProgress && transformStream.on('progress', progress => {
          onDownloadProgress(Object.assign(progress, {
            download: true
          }));
        });
        streams.push(transformStream);
      }
      
      let responseStream = res;
      
      const lastRequest = res.req || req;
      
      if (config.decompress !== false && res.headers['content-encoding']) {
        
        
        if (method === 'HEAD' || res.statusCode === 204) {
          delete res.headers['content-encoding'];
        }
        switch (res.headers['content-encoding']) {
        
        case 'gzip':
        case 'x-gzip':
        case 'compress':
        case 'x-compress':
        case 'deflate':
          
          streams.push(zlib.createUnzip(zlibOptions));
          
          delete res.headers['content-encoding'];
          break;