[Bug]: HopGuiWorkflowGridDelegate does not stop timer for auto refresh when closed

[nadment]

Apache Hop version?

2.10.0-SNAPSHOT

Java version?

Java 17

Operating system

Windows

What happened?

HopGuiWorkflowGridDelegate doesn't stop the auto refresh timer when it's closed, causing thread accumulation.

• I've done a bit of cleanup and adapted to the dark mode
  

Issue Priority

Priority: 3

Issue Component

Component: Hop Gui