[Satellite6] Unable to load the satellite WEBUI after an upgrade from 6.0.8 to 6.1.1

Issue

• Unable to load the Satellite 6 WEBUI after the upgradation.
• Accessing the Satellite 6 WEBUI gives the following error message.

Web application could not be started

PGError: ERROR:  relation "katello_models" does not exist
LINE 4:              WHERE a.attrelid = '"katello_models"'::regclass
                                        ^
:             SELECT a.attname, format_type(a.atttypid, a.atttypmod), d.adsrc, a.attnotnull
              FROM pg_attribute a LEFT JOIN pg_attrdef d
                ON a.attrelid = d.adrelid AND a.attnum = d.adnum
             WHERE a.attrelid = '"katello_models"'::regclass
               AND a.attnum > 0 AND NOT a.attisdropped
             ORDER BY a.attnum
 (ActiveRecord::StatementInvalid)