### Describe the bug

libraries like axios-mock-adapter define an adapter but in same cases need to access to original adapter.

It was working correctly before as the adapter was always a function.
Now it can be an array of string

Only the method getAdapter() in adapters/adapter.js can allow access to original adapters (xhr and http)
But this method is not exported a all at top level.

Can you export it ? 


### To Reproduce

Try to use axios-mock-adapter plugin with onNoMatch option

### Code snippet

_No response_

### Expected behavior

_No response_

### Axios Version

1.2.1 and upper

### Adapter Version

_No response_

### Browser

_No response_

### Browser Version

_No response_

### Node.js Version

_No response_

### OS

_No response_

### Additional Library Versions

_No response_

### Additional context/Screenshots

_No response_
test/specs/instance.spec.js
'CancelToken',
        'isCancel',
        'all',
        'spread',
        'getUri',
        'isAxiosError',
        'mergeConfig',
        'VERSION',
        'default',
        'toFormData',
        'formToJSON',
        'AxiosHeaders',
        'HttpStatusCode'
      ].indexOf(prop) > -1) {
        continue;
      }
      expect(typeof instance[prop]).toBe(typeof axios[prop]);
    }
  });
  it('should make an http request without verb helper', function (done) {
    const instance = axios.create();
    instance('/foo');
    getAjaxRequest().then(function (request) {
      expect(request.url).toBe('/foo');
      done();
    });
  });
  it('should make an http request with url instead of baseURL', function (done) {
    const instance = axios.create({
      url: 'https://api.example.com'