Close #2200 - fix the exception text for wrong classification categoeries

lib/taskana-core-test/src/test/java/acceptance/TaskanaConfigurationTest.java

@@ -958,10 +958,12 @@ class TaskanaConfigurationTest {
       assertThatThrownBy(call)
           .isInstanceOf(InvalidArgumentException.class)
           .hasMessageContaining(
-              "Parameter classificationCategoriesByType "
-                  + "(taskana.classification.categories.<KEY>) "
-                  + "contains invalid Classification Types."
-                  + " configured: [VALID] detected: [DOES_NOT_EXIST]");
+              "Parameter classificationCategoriesByType"
+                  + " (taskana.classification.categories.<KEY>) is configured incorrectly. Please"
+                  + " check whether all specified Classification Types exist. Additionally, check"
+                  + " whether the correct separator is used in the property"
+                  + " taskana.classification.types ."
+          );
     }
 
     @Test

lib/taskana-core/src/main/java/pro/taskana/TaskanaConfiguration.java

@@ -1055,7 +1055,6 @@ public class TaskanaConfiguration {
       this.enforceServiceLevel = enforceServiceLevel;
       return this;
     }
-
     // endregion
 
     // region authentication configuration
@@ -1447,12 +1446,11 @@ public class TaskanaConfiguration {
       if (!new HashSet<>(classificationTypes)
           .containsAll(classificationCategoriesByType.keySet())) {
         throw new InvalidArgumentException(
-            String.format(
                 "Parameter classificationCategoriesByType (taskana.classification.categories.<KEY>)"
-                    + " contains invalid Classification Types. "
-                    + "configured: %s "
-                    + "detected: %s",
-                classificationTypes, classificationCategoriesByType.keySet()));
+                    + " is configured incorrectly. Please check whether all specified"
+                    + " Classification Types exist. Additionally, check whether the correct"
+                    + " separator is used in the property taskana.classification.types ."
+                );
       }
 
       if (!classificationCategoriesByType.keySet().containsAll(classificationTypes)) {