fix exam deletion from SEB Server

Author: anhefti

src/main/java/ch/ethz/seb/sps/server/datalayer/dao/impl/SessionDAOBatis.java

@@ -704,16 +704,12 @@ public Long getNumberOfScreenshots(final String uuid, final FilterMap filterMap)
     public Result<Boolean> hasAnySessionData(Collection<Long> groupIds) {
         return Result.tryCatch(() -> {
 
-            System.out.println("*********************** hasAnySessionData groupIds: " + groupIds);
-
             List<Long> sessionIds = this.sessionRecordMapper
                     .selectIdsByExample()
                     .where(groupId, isIn(groupIds))
                     .build()
                     .execute();
 
-            System.out.println("*********************** hasAnySessionData sessionIds: " + sessionIds);
-
             if (sessionIds == null  || sessionIds.isEmpty()) {
                 return false;
             }
@@ -724,8 +720,6 @@ public Result<Boolean> hasAnySessionData(Collection<Long> groupIds) {
                     .build()
                     .execute();
 
-            System.out.println("*********************** hasAnySessionData dataNum: " + dataNum);
-
             return dataNum != null && dataNum.intValue() != 0;
         });
     }

src/main/java/ch/ethz/seb/sps/server/servicelayer/impl/SessionServiceImpl.java

@@ -186,7 +186,6 @@ public Result<Collection<EntityKey>> closeAllSessions(final Collection<EntityKey
     @Override
     public boolean hasAnySessionDataForExam(final String examUUID) {
         Long pk = examDAO.modelIdToPK(examUUID);
-        System.out.println("*********************** requestDelete pk: " + pk);
         if (pk != null) {
             return this.groupDAO
                     .allIdsForExamsIds(List.of(pk))