Just got a mail from packagist.org

The jangregor/phpstan-prophecy package of which you are a maintainer has
failed to update due to invalid data contained in your composer.json.
Please address this as soon as possible since the package stopped updating.

It is recommended that you use composer validate to check for errors when you
change your composer.json.

Below is the update log which should highlight errors as
"Skipped branch ...":

[Composer\Repository\InvalidRepositoryException]: Some branches contained invalid data and were discarded, it is advised to review the log and fix any issues present in branches

Skipped branch master, Invalid package information:
conflict.phpspec/prophecy : this version constraint cannot possibly match anything (=2.0.0)
conflict.phpunit/phpunit : this version constraint cannot possibly match anything (=10.0.0)