Version 4.4.0 - Full support of PHP 8.0 and 8.1 - dropped 7.4

PHP 7.4 IS NOT LONGER SUPPORTED AND WILL NOT WORK. Expect error 500.

We are aware this may not be a popular decision.

Please accept the rationale of such change:

• Php supported version: we want to stay in the green zone, anything orange is ignored.
• PHP 8.0 brings lots of improvements: stronger typing, JIT... read more here
• Spatie requires in all their updated packages to be in version 8.0 (basically some of our dependencies).

What's Changed

• Fixes #1149 by @nagmat84 in #1154
• Fix diagnostics by @ildyria in #1152
• Upgrade composer and php version by @ildyria in #1145
• bump to version 4.4.0 + remove unnecessary php-intl requirement by @ildyria in #1157
• update codecov.yml by @ildyria in #1158

Full Changelog: v4.3.6...v4.4.0