TINKERPOP-2647 improved plugin error message in Gremlin Console (#3160)

Author: nnmva

CHANGELOG.asciidoc

@@ -26,6 +26,7 @@ image::https://raw.githubusercontent.com/apache/tinkerpop/master/docs/static/ima
 * Fixed bug in server `Settings` where it was referencing a property that was back in 3.3.0 and generating a warning log.
 * Improved performance of `Traversal.lock()` which was being called excessively.
 * Added log entry in `WsAndHttpChannelizerHandler` to catch general errors that escape the handlers.
+* Improved invalid plugin error message in Gremlin Console.
 * Added a `MessageSizeEstimator` implementation to cover `Frame` allowing Gremlin Server to better estimate message sizes for the direct buffer.
 * Fixed bug in Gremlin Console for field accessor issue with JDK17.
 * Improved logging around triggers of the `writeBufferHighWaterMark` so that they occur more than once but do not excessively fill the logs.

gremlin-console/src/main/groovy/org/apache/tinkerpop/gremlin/console/Console.groovy

@@ -158,7 +158,8 @@ class Console {
                 if (!io.quiet)
                     io.out.println(Colorizer.render(Preferences.infoColor, "plugin activated: " + pluggedIn.getPlugin().getName()))
             } else if (!io.quiet) {
-                    io.out.println(Colorizer.render(Preferences.infoColor, "invalid plugin: " + pluginName))
+                io.out.println(Colorizer.render(Preferences.infoColor, "invalid plugin: " + pluginName + " -- removing reference to this plugin."))
+
             }
         }