Expose RestOperations to be configurable for JWKS URI loader

[mnovoseltsev]

Summary

I wanted to set custom rest operations for NimbusJwtDecoderJwkSupport, but it appears that NimbusJwtDecoderJwkSupport instance is created inside of the following private method: OidcAuthorizationCodeAuthenticationProvider#getJwtDecoder (similar for reactive provider). So it is impossible to use NimbusJwtDecoderJwkSupport#setRestOperations method. Also there is no way to pre-populate OidcAuthorizationCodeAuthenticationProvider#jwtDecoders variable with own JWT Decoders.

Actual Behavior

It is not possible to use custom rest operations for fetching keys from the JWKS endpoint. Unless you need to copy-paste whole OidcAuthorizationCodeAuthenticationProvider class to add ability to set custom rest operations.

Expected Behavior

RestOperations setter should be available for configuration similar to org.springframework.security.config.annotation.web.configurers.oauth2.client.OAuth2LoginConfigurer.TokenEndpointConfig#accessTokenResponseClient setter for Token Endpoint.

Version

5.1.2

[jgrandja]

@mnovoseltsev This will be addressed in #5717. Closing this as a duplicate.