Fix: Add support for special characters

[burhandodhy]

Description of the Change

This PR fixes an issue where the special characters get encoded due to the utf8_uri_encode function in sanitize_payload_item and sanitize_payload_args_recursive functions.

Closes #348

How to test the Change

1. Upload or edit a Brightcove video
2. Use a special character in the Name field such as ’, —, or é.
3. Reload the page and confirm the field doesn't have encoded characters anymore

Changelog Entry

Fixed - Add support for special characters

Credits

Props @burhandodhy @cr0ybot

Checklist:

• [ ] I agree to follow this project's Code of Conduct.
• [ ] I have updated the documentation accordingly.
• [ ] I have added tests to cover my change.
• [x] All new and existing tests pass.