Update contexhub stub impl to V4

- Include actual implementation for getHubs()

Test: build
Bug: 361830233
Flag: N/A
Change-Id: Ib6b0d5628fb8f7c88c935e61093cf3f6a3dd0e65
diff --git a/contexthub/aidl/default/contexthub-default.xml b/contexthub/aidl/default/contexthub-default.xml
index 2f8ddc8..359bb0a 100644
--- a/contexthub/aidl/default/contexthub-default.xml
+++ b/contexthub/aidl/default/contexthub-default.xml
@@ -1,7 +1,7 @@
 <manifest version="1.0" type="device">
     <hal format="aidl">
         <name>android.hardware.contexthub</name>
-        <version>3</version>
+        <version>4</version>
         <interface>
             <name>IContextHub</name>
             <instance>default</instance>