Problem Description

Request Participants email subject broken when JIRA's default language is set to Spanish

Steps to Replicate

1. Set JIRA's default language to español (España) via Administration > System > General configuration, update the settings.
2. Create an issue in a JIRA Service Desk project.
3. Go to the issue, add a customer to the Request Participants field.
4. Check the email sent to the customer.

Expected result

The subject of the email sent is admin lo añadió como participante en una solicitud #TEST-1: testing

Actual result

The subject of the email sent is admin te a\u00F1adi\u00F3 como participante en una solicitud #TEST-1: testing