PHP_CodeSniffer users: please read this important announcement: https://github.com/squizlabs/PHP_CodeSniffer/issues/3932
squizlabs/PHP_CodeSniffer is dead, long live PHPCSStandards/PHP_CodeSniffer!
Also, please consider sponsoring the project to safeguard its continuation, as without funding, we'll have the same problem again sooner rather than later.
P.S.: @phpcs now also has its own account, follow it to stay informed.