CurvedAnimations not getting disposed

Hello, I am debugging one of our applications that contains some memory leaks.

We are using the [leak_tracker](https://github.com/dart-lang/leak_tracker) package to debug and get objects not being properly disposed. All of these warnings come from CurvedAnimations not being properly disposed. Moreover, we are using a lot `flutter_animate` for all of our animations, and we declare some `SlideEffects` and `FadeEffects` with a curve.

This is the stacktrace for the `SlideEffect`
```
#7______FlutterMemoryAllocations.dispatchObjectEvent_(package:flutter/src/foundation/memory_allocations.dart:243:23)
#8______FlutterMemoryAllocations.dispatchObjectCreated_(package:flutter/src/foundation/memory_allocations.dart:282:5)
#9______new_CurvedAnimation_(package:flutter/src/animation/animations.dart:385:41)
#10_____EffectEntry.buildAnimation_(package:flutter_animate/src/flutter_animate.dart:59:12)
#11_____Effect.buildAnimation_(package:flutter_animate/src/effects/effect.dart:52:10)
#12_____SlideEffect.build_(package:flutter_animate/src/effects/slide_effect.dart:38:17)
#13______AnimateState.build_(package:flutter_animate/src/animate.dart:398:28)
#14_____StatefulElement.build_(package:flutter/src/widgets/framework.dart:5841:27)
#15_____ComponentElement.performRebuild_(package:flutter/src/widgets/framework.dart:5733:15)
#16_____StatefulElement.performRebuild_(package:flutter/src/widgets/framework.dart:5892:11)
#17_____Element.rebuild_(package:flutter/src/widgets/framework.dart:5445:7)
#18_____ComponentElement._firstBuild_(package:flutter/src/widgets/framework.dart:5715:5)
#19_____StatefulElement._firstBuild_(package:flutter/src/widgets/framework.dart:5883:11)
#20_____ComponentElement.mount_(package:flutter/src/widgets/framework.dart:5709:5)
#21_____Element.inflateWidget_(package:flutter/src/widgets/framework.dart:4555:16)
```

Is it possible that Effects are not disposing well its `CurvedAnimation`? By looking at the code I can't find where it is disposed.