Fixed Invalid date value on assets acceptance mail notification

[inietov]

Description

The date acceptance data that is passed to the notification was being generated wrong as it used to take the format that the app have set to show in the interface. This PR pass the needed dates as YYYY-MM-DD always, and then the mail notification is shown as the user have it configured.

Fixes internal freshdesk 32971

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Test Configuration:

• PHP version: 8.2
• MySQL version: 8.0.31
• Webserver version: PHP development Server
• OS version: Debian 11

[what-the-diff]

• Changed the date format from $branding_settings->date_display_format to 'Y-m-d'
• Added a new line in the declined email template with {{declined_date}}