Enhancement - Form submission message display location options

[Sujit-shrestha]

All Submissions:

• Have you followed the Everest Forms Contributing guideline?
• Does your code follow the WordPress' coding standards?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changes proposed in this Pull Request:

This PR introduces enhancement in form submission message display. The user can set where the message is displayed.

How to test the changes in this Pull Request:

1. Go-to free version of Everest-forms. Create a form and goto the settings of the form.
2. Choose one of location in "Success message display option" using the dropdown in Setitngs>Confirmation and save the settings.
3. Test where the success message appears by submitting the form. You can submit the form by embedding it in any of the pages.

Types of changes:

• Bug fix (non-breaking change which fixes an issue)
• Enhancement (modification of the currently available functionality)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Other information:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you successfully ran tests with your changes locally?
• Have you updated the documentation accordingly?

Changelog entry

Enhancement - Form submission message display options.

[joshianup1]

LGTM ✅