Service Desk SLA Calendar cannot create holiday in Firefox and IE11. This issue also happened when we change the language to French

**Summary**

When trying to add a holiday in the SLA Calendar by using Firefox and IE, it will return an error. Service Desk also does not recognize French months in the date.

**Steps to Reproduce 1**

1. Set the default language and profile language in JIRA to French
2. Go to Service Desk
3. Create a new SLA Calendar
4. Add any holiday
5. Service Desk will throw an error: Invalid Date Format
   

**Steps to Reproduce 2**

1. Go to Service Desk by using Firefox or IE11
2. Create a new SLA Calendar
3. Add any date holiday
4. Service Desk will throw an error: Invalid Date Format
   

**Workaround**

1. Configure the holiday by using Chrome.
2. Change the profile language to English
3. Add the holiday in the SLA Calendar