Popup Plugin For WordPress - ConvertPlus 3.5.29

- Improvement: Improved code quality syntax and security checks for better coding standards and practices.
- Fix: Resolved PHP deprecated errors.

- Improvement: Compatibility with WordPress version 6.6.
- Fix: Country names containing spaces were not being saved correctly in the select country option.
- Fix: Improved codebase for better security.
- Fix: Google reCAPTCHA showing error for site key.
- Fix: Lint CSS and JS errors fixes.
- Fix: Undefined function causing fatal error.

Improved security.
Resolved WordPress deprecation errors.
PHP errors and warnings.