migrate from CAS to Oauth2-JWT Auth (#197)

Co-authored-by: Michael Hoennig <michael@hoennig.de>
Reviewed-on: https://dev.hostsharing.net/hostsharing/hs.hsadmin.ng/pulls/197
Reviewed-by: Marc Sandlus <marc.sandlus@hostsharing.net>

src/test/resources/application.yml

@@ -46,12 +46,9 @@ logging:
         # just for the case there are problems with Testcontainers/Docker integration
         # org.testcontainers: DEBUG
         # com.github.dockerjava: DEBUG
+        # org.springframework.security: DEBUG
 
 testcontainers:
     network:
         mode: host
 
-hsadminng:
-    cas:
-        server: http://localhost:8088/cas # mocked via WireMock
-        service: http://localhost:8080/api # must match service used in WireMock mock response