Add childlock module for vacuums (#1461)

Add new configuration feature:
```
Child lock (child_lock): False
```
---------

Co-authored-by: Steven B. <51370195+sdb9696@users.noreply.github.com>

kasa/smart/modules/childlock.py

@@ -0,0 +1,37 @@
+"""Child lock module."""
+
+from __future__ import annotations
+
+from ...feature import Feature
+from ..smartmodule import SmartModule
+
+
+class ChildLock(SmartModule):
+    """Implementation for child lock."""
+
+    REQUIRED_COMPONENT = "button_and_led"
+    QUERY_GETTER_NAME = "getChildLockInfo"
+
+    def _initialize_features(self) -> None:
+        """Initialize features after the initial update."""
+        self._add_feature(
+            Feature(
+                device=self._device,
+                id="child_lock",
+                name="Child lock",
+                container=self,
+                attribute_getter="enabled",
+                attribute_setter="set_enabled",
+                type=Feature.Type.Switch,
+                category=Feature.Category.Config,
+            )
+        )
+
+    @property
+    def enabled(self) -> bool:
+        """Return True if child lock is enabled."""
+        return self.data["child_lock_status"]
+
+    async def set_enabled(self, enabled: bool) -> dict:
+        """Set child lock."""
+        return await self.call("setChildLockInfo", {"child_lock_status": enabled})