feat: Implement oauth2 monitors (#3119)

* [empty commit] pull request for implement oauth2 monitor

* feat: implement oauth2 client credentials flow

* fix: auth methods clarification & error handling

* docs: fix JSdocs types and clarifications

server/database.js

@@ -75,6 +75,7 @@ class Database {
         "patch-added-json-query.sql": true,
         "patch-added-kafka-producer.sql": true,
         "patch-add-certificate-expiry-status-page.sql": true,
+        "patch-monitor-oauth-cc.sql": true,
     };
 
     /**