Decouple from lcobucci/clock in favour of psr/clock

[okorneliuk]

Hello everyone,

The problem: my application is currently in the state of having 3 implementations of psr/clock. I want to reduce this quantity to 1.

I noticed, that this bundle uses mostly $clock->now() fuctionality from psr/clock and there is only one place, where SystemClock is used (we can get rid of it too). We can easily decouple from lcobucci/clock so will be able to use another implementation of psr/clock. For example, if you have this bundle v3, you have symfony/clock already installed for sure, because symfony/security-bundle v6.3+ depends of it.

As of system clock, having Psr/Clock interface instead of nullable class in the argument of the service, we will be able to replace it easily if there is such a demand for testing or else.

Is it worth to create a PR and implement all of these there?