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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
})
        }).then(function (res) {
          assert.equal(res.data, '123456789', 'should pass through proxy');
          done();
        }).catch(done);
      });
    });
  });
  it('should re-evaluate proxy on redirect when proxy set via env var', function (done) {
    process.env.http_proxy = 'http://localhost:4000'
    process.env.no_proxy = 'localhost:4000'
    var proxyUseCount = 0;
    server = http.createServer(function (req, res) {
      res.setHeader('Location', 'http://localhost:4000/redirected');
      res.statusCode = 302;
      res.end();
    }).listen(4444, function () {
      proxy = http.createServer(function (request, response) {
        var parsed = url.parse(request.url);
        if (parsed.pathname === '/redirected') {
          response.statusCode = 200;
          response.end();
          return;
        }
        proxyUseCount += 1;
        var opts = {
          host: parsed.hostname,
          port: parsed.port,
          path: parsed.path,
          protocol: parsed.protocol,