sessionLock: fix misc:allow_session_lock_restore

[PaideiaDilemma]

Describe your PR, what does it fix/add?

I broke misc:allow_session_lock_restore with #6843.
The session beeing locked is checked in the onNewSessionLock handler, which also respects the
misc:allow_session_lock_restore option. So i removed the check in CSessionLockProtocol::onLock.

Closes #7455

Is there anything you want to mention? (unchecked code, possible bugs, found problems, breaking compatibility, etc.)

The misc:allow_session_lock_restore option is a bit dangerous when hyprlock is configured with grace is used.
For example when a idle deamon lanches hyprlock a second time without --immediate and then the session can sudently be unlocked via grace.

Maybe we should ad a disclaimer to the grace option in the wiki.

Is it ready for merging, or does it need work?

Tested it, seems to behave as expected.

• crash handler of hyprlock can recover the session.
• when the option is disabled it does not work and new hyprlock instances recieve finished
• launching a second hyprlock instance with the option enabled results in two locks, which seems to work, except the grace problem mentioned above.