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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
const proxyHost = proxy.hostname || proxy.host;
    options.hostname = proxyHost;
    
    options.host = proxyHost;
    options.port = proxy.port;
    options.path = location;
    if (proxy.protocol) {
      options.protocol = proxy.protocol.includes(':') ? proxy.protocol : `${proxy.protocol}:`;
    }
  }
  options.beforeRedirects.proxy = function beforeRedirect(redirectOptions) {
    
    
    setProxy(redirectOptions, configProxy, redirectOptions.href);
  };
}
const isHttpAdapterSupported = typeof process !== 'undefined' && utils.kindOf(process) === 'process';
export default isHttpAdapterSupported && function httpAdapter(config) {
  return new Promise(function dispatchHttpRequest(resolvePromise, rejectPromise) {
    let data = config.data;
    const responseType = config.responseType;
    const responseEncoding = config.responseEncoding;
    const method = config.method.toUpperCase();
    let isFinished;
    let isDone;
    let rejected = false;
    let req;
    
    const emitter = new EventEmitter();
    function onFinished() {