Add removed webview_zygote_socket to 27 mapping file.

Bug: 69390067
Test: manual run of treble_sepolicy_tests
Change-Id: I19252eb743e6527cbe262b1e066a3f67f7186994
diff --git a/private/compat/27.0/27.0.cil b/private/compat/27.0/27.0.cil
index 2272903..1be82bf 100644
--- a/private/compat/27.0/27.0.cil
+++ b/private/compat/27.0/27.0.cil
@@ -1,4 +1,5 @@
 ;; types removed from current policy
+(type webview_zygote_socket)
 (type reboot_data_file)
 
 (expandtypeattribute (accessibility_service_27_0) true)