Update docs (17824)

Signed-off-by: Nester.zhou <ester.zhou@huawei.com>

en/release-notes/changelogs/OpenHarmony_4.0.6.3/changelogs-arkui.md

+# ArkUI Subsystem Changelog
+Fixed the issue where the layout of child components in the [\<Stack>](../../../application-dev/reference/arkui-ts/ts-container-stack.md) container does not follow the **alignContent** settings when the child components do not fit in the container.
+
+Example:
+
+```ts
+@Entry
+@Component
+struct StackExample {
+  build() {
+    Stack({alignContent:Alignment.TopEnd}){
+      Text('First child, show in bottom')
+        .width(200).height(200).backgroundColor(0xd2cab3).margin(10)
+    }.width(150).height(150).backgroundColor(Color.Pink).margin(100)
+  }
+}
+```
+Before: Child components are not arranged based on **alignContent:Alignment.TopEnd**.
+
+![stack](figures/stack_before.jpg)
+
+After: Child components are arranged based on **alignContent:Alignment.TopEnd**.
+
+![stack](figures/stack_after.jpg)
+
+
+**Change Impact**
+
+The previous workaround – setting the **Offset** or **translate** attribute – needs to be removed.
+
+**Adaptation Guide**
+
+Remove the **Offset** and **translate** settings for the child components and use **alignContent** for layout.