* Fix PHP 8.1 deprecation warnings on Helper and FormHelper
- fix deprecation warning when Helper::_entityPath is null
- fix `strftime` function deprecation warning on FormHelper::_getDateTimeValue method
ref: ARCH-11
* Switch deprecated utf8_encode function to mb_convert_encoding function
ref: ARCH-13
* Hide strftime deprecation warning
Since CakePHP 2 doesn't require the installation of `intl` PHP extension in it's documentation, I can't use the alternative `IntlDateFormatter::format` because it relies such extension.
ref: ARCH-13
* Roll back the use of strftime
ref: ARCH-11
* Fix preg_split subject param null deprecated on FormHelper::dateTime
* Fix preg_split deprecated null param limit on CakeResponse::checkNotModified
* fix: get rid of (some) PHP deprecation warnings
- CakeResponse.php strotime() and preg_split() warnings
* Ignore hide srtftime function deprecation warning from PHPCS
* Fix typo on phpcs ignore comments
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Co-authored-by: Jan Pešek <jan@sinch.cz>
