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#### Describe the bug
The timeoutErrorMessage property in config not work with Node.js, expected custom error message, got "**timeout of \*ms exceeded**"

#### To Reproduce
```js
it('should respect the timeoutErrorMessage property', function (done) {

    server = http.createServer(function (req, res) {
      setTimeout(function () {
        res.end();
      }, 1000);
    }).listen(4444, function () {
      var success = false, failure = false;
      var error;

      axios.get('http://localhost:4444/', {
        timeout: 250,
        timeoutErrorMessage: 'oops, timeout',
      }).then(function (res) {
        success = true;
      }).catch(function (err) {
        error = err;
        failure = true;
      });

      setTimeout(function () {
        assert.strictEqual(success, false, 'request should not succeed');
        assert.strictEqual(failure, true, 'request should fail');
        assert.strictEqual(error.code, 'ECONNABORTED');
        assert.strictEqual(error.message, 'oops, timeout');
        done();
      }, 300);
    });
});
```

#### Expected behavior
Expected: oops, timeout
Got: timeout of 250ms exceeded

#### Environment
- Axios Version: 0.21.1
- Adapter: HTTP
- Browser: none
- Browser Version: none
- Node.js Version: 12.19.0
- OS: MacOS 10.14
- Additional Library Versions: none

#### Additional context/Screenshots
![image](https://user-images.githubusercontent.com/10591960/105522169-dbe85700-5d17-11eb-963e-191b8581f665.png)



test/unit/adapters/http.js
assert.equal(res.data, '4567', 'should not use proxy for domains in no_proxy');
          done();
        });
      });
    });
  });
  it('should use proxy for domains not in no_proxy', function (done) {
    server = http.createServer(function (req, res) {
      res.setHeader('Content-Type', 'text/html; charset=UTF-8');
      res.end('4567');
    }).listen(4444, function () {
      proxy = http.createServer(function (request, response) {
        var parsed = url.parse(request.url);
        var opts = {
          host: parsed.hostname,
          port: parsed.port,
          path: parsed.path
        };
        http.get(opts, function (res) {
          var body = '';
          res.on('data', function (data) {
            body += data;
          });
          res.on('end', function () {
            response.setHeader('Content-Type', 'text/html; charset=UTF-8');
            response.end(body + '1234');
          });
        });
      }).listen(4000, function () {
        // s