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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
headers: {
            'Content-Type': 'multipart/form-data'
          }
        }).then(function (res) {
          assert.deepStrictEqual(res.data.fields, {foo: 'bar'});
          assert.strictEqual(res.data.files.file1.mimetype, 'image/jpeg');
          assert.strictEqual(res.data.files.file1.originalFilename, 'temp/bar.jpg');
          assert.strictEqual(res.data.files.file1.size, 3);
          done();
        }).catch(done);
      });
    });
    describe('toFormData helper', function () {
      it('should properly serialize nested objects for parsing with multer.js (express.js)', 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.post('/', multer().none(), function (req, res, next) {
          res.send(JSON.stringify(req.body));
        });
        server = app.listen(3001, function () {
          // mu
          // ar
          // ar
          // --
          // ar