Export client-authentication and user-authentication middlewares

[rashisf]

Description
Currently, the ClientAuthenticationMiddlewareProvider and UserAuthenticationMiddlewareProvider middlewares are not exported.

Though the bindings are created by setting useClientAuthenticationMiddleware and useUserAuthenticationMiddleware to true, they are chained to RestTags.REST_MIDDLEWARE_CHAIN which is the default middlware chain.

The middlewares are not exported and hence custom actions (like defining the middleware chain) cannot be configured onto them.

Describe the solution you'd like
Exposing and exporting these middlewares, one can easily customize and chain these middlewares in their sequences other than the default behavious.

Export them using the index.ts file.

They can be imported and customized.

import {ClientAuthenticationMiddlewareProvider} from 'loopback4-authentication';
...
...
this.middleware(ClientAuthenticationMiddlewareProvider, {
// custom options
chain: MiddlwareChain.PRE_INVOKE
});

[yeshamavani]

@rashisf would you like to contribute

[rashisf]

@rashisf would you like to contribute

Yes