Leaked disposable in RectangleRenderer

[Tyriar]

Repro:

1. Open Code OSS, enable gpu
2. Open terminalInstance.ts
3. Open runInTerminalTool.ts, switch between them a few times

[rzhao271]

I don't see any more errors for RectangleRenderer. If I switch between the tabs really quickly by only having those two open and holding down Ctrl+PgDn, I see a new one:

lifecycle.ts:52 [LEAKED DISPOSABLE] Error: CREATED via:
    at GCBasedDisposableTracker.trackDisposable (lifecycle.ts:56:17)
    at trackDisposable (lifecycle.ts:272:21)
    at new Disposable (lifecycle.ts:538:3)
    at new ViewEventHandler (viewEventHandler.ts:14:3)
    at new BaseRenderStrategy (baseRenderStrategy.ts:28:3)
    at new ViewportRenderStrategy (viewportRenderStrategy.ts:90:3)
    at InstantiationService._createInstance (instantiationService.ts:162:18)
    at InstantiationService.createInstance (instantiationService.ts:128:18)
    at ViewLinesGpu._refreshRenderStrategy (viewLinesGpu.ts:340:61)
    at ViewLinesGpu.renderText (viewLinesGpu.ts:476:9)
    at viewLinesGpu.ts:95:12