Add prudential.com to high trust sender domains (#687)

Co-authored-by: Sorted Order Validation <[email protected]>

Author: peterdj45

high_trust_sender_root_domains.txt

@@ -378,6 +378,7 @@ powerapps.com
 primevideo.com
 principal.com
 proxyvote.com
+prudential.com
 pulley.com
 pwc.com
 q4inc.com