Fixing error with non existent class

[dblancaster]

$entityClass was updating from:

"Oro_Bundle_OrganizationBundle_Entity_BusinessUnit"

to:

"Proxies/CG/Oro_Bundle_OrganizationBundle_Entity_BusinessUnit"

Which causes

Fatal error: require(): Failed opening required '/var/www/html/demo/var/cache/prod/doctrine/orm/Proxies/___CG___Oro_Bundle_OrganizationBundle_Entity_BusinessUnit.php'

When attempting to add an attachment on a Business Unit, reproduced here:
First add attachments to business units in the entity configuration:
https://demo.orocrm.com/index.php/organization/business_unit/view/1

Once an attachment has been added to the Business Unit, this incorrect URL is generated:
https://demo.orocrm.com/index.php/attachment/create/Proxies___CG___Oro_Bundle_OrganizationBundle_Entity_BusinessUnit/1?_widgetContainer=dialog&_wid=ee7ba2d3-5903-4207-a15a-3bebce87ff1f&_widgetInit=1

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[mbessolov]

Thank you for the report and the proposed fix!

(internal reference: BAP-20386)