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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
// ar
          // --
          // ar
          // ar
          // --
          Promise.all([null, false, true].map(function (mode) {
            return axios.postForm('http://localhost:3001/', obj, {formSerializer: {indexes: mode}})
              .then(function (res) {
                assert.deepStrictEqual(res.data, obj, 'Index mode ' + mode);
              });
          })).then(function (){
            done();
          }, done)
        });
      });
    });
  });
  describe('URLEncoded Form', function () {
    it('should post object data as url-encoded form if content-type is application/x-www-form-urlencoded', function (done) {
      var app = express();
      var obj = {
        arr1: ['1', '2', '3'],
        arr2: ['1', ['2'], '3'],
        obj: {x: '1', y: {z: '1'}},
        users: [{name: 'Peter', surname: 'griffin'}, {name: 'Thomas', surname: 'Anderson'}]
      };
      app.use(bodyParser.urlencoded({ extended: true }));
      app.post('/', function (req, res, next) {
        res.send(JSON.stringify(req.body));
      });