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#### Describe the bug

`config.paramsSerializer.indexes = false` (default) adds indexes if an object is inside an array but it shouldn't.

#### To Reproduce

https://runkit.com/doits/634530f2d3a446000813ef73

```js
var axios = require("axios")

const req = await axios.get('https://www.example.com', { params: { a: [{ name: 'abc' }], b: ['x', 'y'] } })

console.log(req.request.path)

// => "/?a[0][name]=abc&b[]=x&b[]=y"
```

#### Expected behavior

No `a[0]` but `a[]`:

```js
// => "/?a[][name]=abc&b[]=x&b[]=y"
```

#### Environment
 - Axios Version 1.1.2

#### Additional context/Screenshots

None

test/typescript/axios.ts
.then(handleResponse)
  .catch(handleError);
instance1.options('/user')
  .then(handleResponse)
  .catch(handleError);
instance1.get('/user', { params: { id: 12345 } })
  .then(handleResponse)
  .catch(handleError);
instance1.post('/user', { foo: 'bar' })
  .then(handleResponse)
  .catch(handleError);
instance1.post('/user', { foo: 'bar' }, { headers: { 'X-FOO': 'bar' } })
  .then(handleResponse)
  .catch(handleError);
axios.defaults.headers['X-FOO'];
axios.defaults.baseURL = 'https://api.example.com/';
axios.defaults.headers.common['Authorization'] = 'token';
axios.defaults.headers.post['X-FOO'] = 'bar';
axios.defaults.timeout = 2500;
instance1.defaults.baseURL = 'https://api.example.com/';
instance1.defaults.headers.common['Authorization'] = 'token';
instance1.defaults.headers.post['X-FOO'] = 'bar';
instance1.defaults.timeout = 2500;
axios.create({ headers: { foo: 'bar' } });
axios.create({ headers: { common: { foo: 'bar' } } });
axios.create({
  headers: {
    'Content-Type': 'application/json',
  },
  formSerializer: {