add message to error responses

Some Spring update changed the default behavior to not include the
message in error responses.

pdb-ui/src/main/resources/application.properties

@@ -9,6 +9,9 @@ path.fileDropConfig=${base.dir}/drop.json
 logging.config=classpath:log4j2.xml
 
 server.port=17333
+server.error.include-message=ALWAYS
+server.error.include-stacktrace=NEVER
+
 
 spring.servlet.multipart.enabled=true
 spring.servlet.multipart.max-file-size=3000MB