Improve custom validation message for array constraints (#93)

* Issue: wso2-enterprise/open-healthcare#1664

native/fhir-to-bal-lib/src/main/resources/templates/fhir_resource.vm

@@ -88,14 +88,14 @@ public type $util.resolveSpecialCharacters($resourceName) record {|
 #if( $element.getMin() == $min )
         minLength: {
             value: $min$separator
-            message: "This field must be an array containing at least one item."
+            message: "Validation failed for $.$element.getPath() constraint. This field must be an array containing at least one item."
         }#if( $element.getMax() == $max )$separator#end
 #end
 
 #if( $element.getMax() == $max )
         maxLength: {
             value: $max$separator
-            message: "This field must be an array containing at most one item."
+            message: "Validation failed for $.$element.getPath() constraint. This field must be an array containing at most one item."
         }
 #end
     }
@@ -163,14 +163,14 @@ public type $util.resolveSpecialCharacters($extendedElement.getTypeName()) recor
 #if( $childElement.getMin() == $min )
         minLength: {
             value: $min$separator
-            message: "This field must be an array containing at least one item."
+            message: "Validation failed for $.$childElement.getPath() constraint. This field must be an array containing at least one item."
         }#if( $childElement.getMax() == $max )$separator#end
 #end
 
 #if( $childElement.getMax() == $max )
         maxLength: {
             value: $max$separator
-            message: "This field must be an array containing at most one item."
+            message: "Validation failed for $.$childElement.getPath() constraint. This field must be an array containing at most one item."
         }
 #end
     }