Spring Security First class test support for spring-security-oauth2-client

Summary

We should add first-class test support for the spring-security-oauth2-client module

• [x] #7618 - Add OIDC Login MockMvc Test Support
• [x] #7680 - Add OIDC Login Reactive Test Support
• [x] #7789 - Add OAuth 2.0 Login MockMvc Test Support
• [x] #7828 - Add OAuth 2.0 Login Reactive Test Support
• [x] #7886 - Add OAuth 2.0 Client MockMvc Test Support
• [x] #7910 - Add OAuth 2.0 Client Reactive Test Support

Comment From: ch4mpy

I may have the beginning of solution. More details

Comment From: elch78

Added another ticket that also relates to test support #7624

Comment From: jgrandja

@jzheaux I know you were involved in helping merge some of the oauth2-client test support. Can this be closed now?

Comment From: jzheaux

Yes @jgrandja, this was solved in #7618, #7680, #7789, #7828, #7886 and #7910. I've added those to the description for clarity.