Fix memory leak on iOS (#1292)

## Proposed Changes

Remove views from superviews to break some retain cycle.

## Testing

Test: TODO

## Issues Fixed

Fixes: JetBrains/compose-multiplatform#4626

compose/mpp/demo/src/uikitMain/kotlin/androidx/compose/mpp/demo/bugs/IosBugs.kt

@@ -37,4 +37,5 @@ val IosBugs = Screen.Selection(
     ComposeAndNativeScroll,
     MeasureAndLayoutCrash,
     AnimationFreezeBug,
+    ModalMemoryLeak
 )

compose/mpp/demo/src/uikitMain/kotlin/androidx/compose/mpp/demo/bugs/ModalMemoryLeak.kt

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package androidx.compose.mpp.demo.bugs
+
+import androidx.compose.foundation.layout.height
+import androidx.compose.material.Button
+import androidx.compose.material.ExperimentalMaterialApi
+import androidx.compose.material.MaterialTheme
+import androidx.compose.material.ModalBottomSheetValue
+import androidx.compose.material.Text
+import androidx.compose.material.rememberModalBottomSheetState
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.ModalBottomSheet
+import androidx.compose.mpp.demo.Screen
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import androidx.compose.material3.rememberModalBottomSheetState
+import androidx.compose.runtime.DisposableEffect
+import platform.posix.free
+import platform.posix.malloc
+
+@OptIn(ExperimentalMaterial3Api::class, ExperimentalMaterialApi::class)
+val ModalMemoryLeak = Screen.Example("ModalMemoryLeak") {
+    MaterialTheme {
+        var openBottomSheet by remember { mutableStateOf(false) }
+        Button(onClick = {
+            openBottomSheet = true
+        }) {
+            Text("ModalBottomSheet3")
+        }
+
+        if (openBottomSheet) {
+            val sheetState = rememberModalBottomSheetState()
+
+            ModalBottomSheet(
+                onDismissRequest = {
+                    openBottomSheet = false
+                },
+                sheetState = sheetState,
+            ) {
+                DisposableEffect(Unit) {
+                    val a = malloc((20_000 * 1024).toULong())
+
+                    onDispose {
+                        println("Disposed")
+                        free(a)
+                    }
+                }
+                Text("ModalBottomSheet3", Modifier.height(500.dp))
+            }
+        }
+    }
+}

compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/scene/ComposeSceneMediator.uikit.kt

@@ -506,6 +506,8 @@ internal class ComposeSceneMediator(
         renderingView.dispose()
         interactionView.dispose()
         rootView.removeFromSuperview()
+        interactionView.removeFromSuperview()
+        renderingView.removeFromSuperview()
         scene.close()
         // After scene is disposed all UIKit interop actions can't be deferred to be synchronized with rendering
         // Thus they need to be executed now.