Added silenced expiration

[MartiSalaMorral]

This feature allows users to configure an expiration time for silenced jobs. This allows having different expiration times between completed and silenced jobs.

If silenced expiration is not present, it uses the completed expiration time by default.

[taylorotwell]

Thanks for your pull request to Laravel!

Unfortunately, I'm going to delay merging this code for now. To preserve our ability to adequately maintain the framework, we need to be very careful regarding the amount of code we include.

If possible, please consider releasing your code as a package so that the community can still take advantage of your contributions!

If you feel absolutely certain that this code corrects a bug in the framework, please "@" mention me in a follow-up comment with further explanation so that GitHub will send me a notification of your response.

[MartiSalaMorral]

Hi @taylorotwell, thanks for your answer.

Although this code does not correct a bug, it adds a quality of life improvement that I think is quite interesting.

This allows to set an expire time for the silenced jobs without affecting the completed jobs. I made these changes because the importance of tracking silenced and completed jobs can differ a lot and setting a lower time for the silenced jobs helps to reduce the memory usage.

[mgralikowski]

I was actually thinking about this change now. Since silenced jobs are typically less critical or significant, providing this flexibility is especially valuable.