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#### Describe the bug

I tried to use the function added in #4248 with TypeScript, but got the following error.

```
Property 'clear' does not exist on type 'AxiosInterceptorManager<AxiosRequestConfig<any>>
```

#### To Reproduce

Execution is possible, but type checking fails.

```ts
import axios from "axios";

axios.interceptors.request.clear()
```

#### Expected behavior

Successful type check

#### Environment
 - Axios 1.0.0
 - TypeScript 4.8.4

#### Additional context/Screenshots

index.d.ts
;
  put<T = any, R = AxiosResponse<T>, D = any>(url: string, data?: D, config?: AxiosRequestConfig<D>): Promise<R>;
  patch<T = any, R = AxiosResponse<T>, D = any>(url: string, data?: D, config?: AxiosRequestConfig<D>): Promise<R>;
  postForm<T = any, R = AxiosResponse<T>, D = any>(url: string, data?: D, config?: AxiosRequestConfig<D>): Promise<R>;
  putForm<T = any, R = AxiosResponse<T>, D = any>(url: string, data?: D, config?: AxiosRequestConfig<D>): Promise<R>;
  patchForm<T = any, R = AxiosResponse<T>, D = any>(url: string, data?: D, config?: AxiosRequestConfig<D>): Promise<R>;
}
export interface AxiosInstance extends Axios {
  <T = any, R = AxiosResponse<T>, D = any>(config: AxiosRequestConfig<D>): Promise<R>;
  <T = any, R = AxiosResponse<T>, D = any>(url: string, config?: AxiosRequestConfig<D>): Promise<R>;
  defaults: Omit<AxiosDefaults, 'headers'> & {
    headers: HeadersDefaults & {
      [key: string]: AxiosHeaderValue
    }
  };
}
export interface GenericFormData {
  append(name: string, value: any, options?: any): any;
}
export interface GenericHTMLFormElement {
  name: string;
  method: string;
  submit(): void;
}
export interface AxiosStatic extends AxiosInstance {
  create(config?: CreateAxiosDefaults): AxiosInstance;
  Cancel: CancelStatic;
  CancelToken: CancelTokenStatic;
  Axios: typeof Axios;
  AxiosError: typeof AxiosError;
  readonly VERSION: string;
  isCancel(value: any): value is Cancel;
  all<T>(values: Array<T | Promise<T>>): Promise<T[]>;
  spread<T, R>(callback: (...args: T[]) => R): (array: T[]) => R;
  isAxiosError<T = any, D = any>(payload: any): payload is AxiosError<T, D>;
  toFormData(sourceObj: object, targetFormData?: GenericFormData, options?: FormSerializerOptions): GenericFormData;
  formToJSON(form: GenericFormData|GenericHTMLFormElement): object;
}
declare const axios: AxiosStatic;
export default axios;
