working hasGlobalAdminRole and prepare for Micrometer metrics with Spring Security (#127)

Co-authored-by: Michael Hoennig <michael@hoennig.de>
Reviewed-on: https://dev.hostsharing.net/hostsharing/hs.hsadmin.ng/pulls/127
Reviewed-by: Marc Sandlus <marc.sandlus@hostsharing.net>

src/main/resources/application.yml

@@ -1,6 +1,15 @@
 server:
     port : 8080
 
+management:
+    server:
+        port: 8081
+        address: 127.0.0.1
+    endpoints:
+        web:
+            exposure:
+                include: info, health, metrics
+
 spring:
 
     datasource: