This commit fixes all 1533 PHPCS errors that PHPCBF can fix automatically in the tests/ directory. Before this change there was a total of 3106 PHPCS errors in the WooCommerce repository and now there is 1573 errors.
This will allow indexed ordering by severity.
Add WC_Log_Levels::get_severity_level method to translate severity
integers to level strings. The inverse of WC_Log_Levels::get_level_severity.
Add context to tests.