MockFluidDataStoreRuntime dispose triggers dispose event

[CraigMacomber]

Description

MockFluidDataStoreRuntime dispose triggers dispose event.
This makes it work more like the real version, and may help cleanup resources (or test resource cleanup) in some cases.

I noticed this was missing since node was emitting warnings about memory leaks due to large numbers of subscriptions to this event, and when looking at the code it was never getting triggered.

This makes it possible to trigger the dispose event, however it does not fix the memory leaks in tests causing large numbers of subscriptions to this.

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Pull request overview

This PR aims to bring MockFluidDataStoreRuntime’s disposal behavior closer to the real IFluidDataStoreRuntime by ensuring a dispose-related event is fired when dispose() is called, enabling test code to clean up event subscriptions.

Changes:

• Emit an event from MockFluidDataStoreRuntime.dispose() when the mock runtime is disposed.