#### Is your feature request related to a problem? Please describe.
No.

#### Describe the solution you'd like
#4734 Changed the entire behavior of the params serializer, breaking using any custom functionality on the consumer side. Add a boolean switch to mimic pre 1.x behavior (default is false) and send the params directly to the encode function

#### Describe alternatives you've considered
Tried working with new solution; it did not pan out well and led to more bugs with our requests

index.d.ts
y;
  httpsAgent?: any;
  proxy?: AxiosProxyConfig | false;
  cancelToken?: CancelToken;
  decompress?: boolean;
  transitional?: TransitionalOptions;
  signal?: GenericAbortSignal;
  insecureHTTPParser?: boolean;
  env?: {
    FormData?: new (...args: any[]) => object;
  };
  formSerializer?: FormSerializerOptions;
}
export interface HeadersDefaults {
  common: RawAxiosRequestHeaders;
  delete: RawAxiosRequestHeaders;
  get: RawAxiosRequestHeaders;
  head: RawAxiosRequestHeaders;
  post: RawAxiosRequestHeaders;
  put: RawAxiosRequestHeaders;
  patch: RawAxiosRequestHeaders;
  options?: RawAxiosRequestHeaders;
  purge?: RawAxiosRequestHeaders;
  link?: RawAxiosRequestHeaders;
  unlink?: RawAxiosRequestHeaders;
}
export interface AxiosDefaults<D = any> extends Omit<AxiosRequestConfig<D>, 'headers'> {
  headers: HeadersDefaults;
}
export interface CreateAxiosDefaults<D = any> extends Omit<AxiosRequestConfig<D>, 'headers'> {
  headers?: RawAxiosRequestHeaders | Partial<HeadersDefaults>;
}
export interface AxiosResponse<T = any, D = any>  {
  data: T;
  status: number;
  statusText: string;
  headers: RawAxiosResponseHeaders | AxiosResponseHeaders;
  config: AxiosRequestConfig<D>;
  request?: any;
}
export class AxiosError<T = unknown, D = any> extends Error {
  constructor(
      message?: string,
      code?: string,
      config?: AxiosRequestConfig<D>,
      request?: any,
      response?: AxiosResponse<T, D>
  );
  config?: AxiosRequestConfig<D>;
  code?: string;
  request?: any;
  response?: AxiosResponse<T, D>;
  isAxiosError: boolean;
  status?: number;
  toJSON: () => object;
  cause?: Error;
  static readonly ERR_FR_TOO_MANY_REDIRECTS = "ERR_FR_TOO_MANY_REDIRECTS";
  static readonly ERR_BAD_OPTION_VALUE = "ERR_BAD_OPTION_VALUE";
  static readonly ERR_BAD_OPTION = "ERR_BAD_OPTION";
  static readonly ERR_NETWORK = "ERR_NETWORK";
  static readonly ERR_DEPRECATED = "ERR_DEPRECATED";
  static readonly ERR_BAD_RESPONSE = "ERR_BAD_RESPONSE";
  static readonly ERR_BAD_