refactor: Update package to support php >=8 and Psr Log 2 || 3

[luislard]

Updating dependencies to be able to work with newer Psr/Log BREAKING CHANGE: we are dropping support for PHP 7.x and Psr/Log 1.x

This pull request fixes issue #.

What's Included in This Pull Request

• Drop support for PHP 7.x
• Drop support for Psr/Log 1.x and support Psr/Log 2.x || 3.x
• Update of PHP Unit to v9 since it was required to achieve the goal
• Update of Psalm since it was required to achieve the goal
• Require the test class from the new package since the test folder was deleted from the source
• Added new strategy in the matrix of PHPUnit testing to use --prefer-lowest and resolve to psr/log v2 during the installation
• Added other PHP static analysis using with different PHP versions
• Fixed Psalm issues mostly adding new annotations since Psalm does not know about different WP versions
• Updated PHPUnit config to remove dprecation warning
• Changed the usage of assertRegexp in test to the new method as it will be deprecated in PHPUnit 10