simplify tests to not reload all users from db at setup

java/com.sap.sse.security.test/src/com/sap/sse/security/jaxrs/api/SecurityResourceTest.java

@@ -52,7 +52,7 @@ public class SecurityResourceTest {
         try {
             store = new UserStoreImpl("TestDefaultTenant");
             store.ensureDefaultRolesExist();
-            store.loadAndMigrateUsers();
+            store.ensureDefaultTenantExists();
             accessControlStore = new AccessControlStoreImpl(store);
             Activator.setTestStores(store, accessControlStore);
             service = new SecurityServiceImpl(/* mailServiceTracker */ null,

java/com.sap.sse.security.test/src/com/sap/sse/security/test/LoginTest.java

@@ -52,7 +52,7 @@ public class LoginTest {
         db.getCollection(CollectionNames.PREFERENCES.name()).drop();
         userStore = new UserStoreImpl(DEFAULT_TENANT_NAME);
         userStore.ensureDefaultRolesExist();
-        userStore.loadAndMigrateUsers();
+        userStore.ensureDefaultTenantExists();
         accessControlStore = new AccessControlStoreImpl(userStore);
         
         Activator.setTestStores(userStore, accessControlStore);

java/com.sap.sse.security.test/src/com/sap/sse/security/test/PermissionCheckerTest.java

@@ -68,7 +68,7 @@ public class PermissionCheckerTest {
         final String adminTenantName = "admin-tenant";
         userStore = new UserStoreImpl(adminTenantName);
         userStore.ensureDefaultRolesExist();
-        userStore.loadAndMigrateUsers();
+        userStore.ensureDefaultTenantExists();
         accessControlStore = new AccessControlStoreImpl(userStore);
         AbstractCompositeAuthorizingRealm.setTestStores(userStore, accessControlStore);
         realm = new UsernamePasswordRealm();

java/com.sap.sse.security.test/src/com/sap/sse/security/test/UserStoreWithPersistenceTest.java

@@ -79,7 +79,7 @@ public class UserStoreWithPersistenceTest {
         try {
             store = new UserStoreImpl("TestDefaultTenant");
             store.ensureDefaultRolesExist();
-            store.loadAndMigrateUsers();
+            store.ensureDefaultTenantExists();
         } catch (UserGroupManagementException | UserManagementException e) {
             throw new RuntimeException(e);
         }