Check package name format before using it for SPA nav

Bug: b/372895305
Test: unit test
Flag: EXEMPT bug fix
Change-Id: Ife615c78c48a2d6f5b938c880c9c2128c5551644

src/com/android/settings/spa/SpaAppBridgeActivity.kt

@@ -38,7 +38,7 @@ class SpaAppBridgeActivity : Activity() {
 
     companion object {
         fun getDestinationForApp(destinationPrefix: String, intent: Intent): String? {
-            val packageName = intent.data?.schemeSpecificPart ?: return null
+            val packageName = intent.data?.schemeSpecificPart?.takeIf { Regex("^([a-zA-Z]\\w*\\.)*[a-zA-Z]\\w*$").matches(it) } ?: return null
             return "$destinationPrefix/$packageName/${UserHandle.myUserId()}"
         }
     }