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#### Describe the issue
Passing Uint8Array or Buffer to postForm results in "source.on is not a function" exception.

#### Example Code
```js
const data = Uint8Array.from([1, 2, 3])
axios.postForm('http://some.url', { data })

// or

const data = Uint8Array.from([1, 2, 3])
axios.postForm('http://some.url', { data: Buffer.from(data) })
```

#### Expected behavior, if applicable
axios should POST a field "data" with the content of the Uint8Array / Buffer

#### Environment
 - Axios Version 0.27.2
 - Node.js Version 18.2.0
 - OS: Windows 11

#### Additional context/Screenshots
Code is compiled from TypeScript using typescript 4.6.4 and a tsconfig.json that extends @tsconfig/node18/tsconfig.json

I am trying to upload the PDF output of puppeteer.


What am I doing wrong?
test/unit/adapters/http.js
res.setHeader('Content-Type', 'application/json');
      var bomBuffer = Buffer.from([0xEF, 0xBB, 0xBF])
      var jsonBuffer = Buffer.from(JSON.stringify(data));
      res.end(Buffer.concat([bomBuffer, jsonBuffer]));
    }).listen(4444, function () {
      axios.get('http://localhost:4444/').then(function (res) {
        assert.deepEqual(res.data, data);
        done();
      }).catch(done);;
    });
  });
  it('should redirect', function (done) {
    var str = 'test response';
    server = http.createServer(function (req, res) {
      var parsed = url.parse(req.url);
      if (parsed.pathname === '/one') {
        res.setHeader('Location', '/two');
        res.statusCode = 302;
        res.end();
      } else {
        res.end(str);
      }
    }).listen(4444, function () {
      axios.get('http://localhost:4444/one').then(function (res) {
        assert.equal(res.data, str);
        assert.equal(res.request.path, '/two');
        done();
      }).catch(done);
    });
  });