Keycloak auth adapter (#6376)

* Copy auth adapter to create keycloak adapter

* Add keycloak authentication adapter

* Add keycloak to auth adapter tests

* Improve tests

Co-authored-by: Rhuan <rhuan@MacBook-Pro-de-Rhuan.local>
Co-authored-by: Diamond Lewis <findlewis@gmail.com>
Co-authored-by: Antonio Davi Macedo Coelho de Castro <adavimacedo@gmail.com>

src/Adapters/Auth/index.js

@@ -22,6 +22,7 @@ const weibo = require('./weibo');
 const oauth2 = require('./oauth2');
 const phantauth = require('./phantauth');
 const microsoft = require('./microsoft');
+const keycloak = require('./keycloak');
 const ldap = require('./ldap');
 
 const anonymous = {
@@ -56,6 +57,7 @@ const providers = {
   weibo,
   phantauth,
   microsoft,
+  keycloak,
   ldap,
 };