GH-310 - Revert "Remove time zone from Postgres event publication schema."

This reverts commit 19457cd. Related ticket: GH-306.

Author: odrotbohm

spring-modulith-events/spring-modulith-events-jdbc/src/main/resources/schema-postgresql.sql

@@ -4,7 +4,7 @@ CREATE TABLE IF NOT EXISTS event_publication
   listener_id      TEXT NOT NULL,
   event_type       TEXT NOT NULL,
   serialized_event TEXT NOT NULL,
-  publication_date TIMESTAMP NOT NULL,
-  completion_date  TIMESTAMP,
+  publication_date TIMESTAMP WITH TIME ZONE NOT NULL,
+  completion_date  TIMESTAMP WITH TIME ZONE,
   PRIMARY KEY (id)
 )