[kdump] Capture more commands for RH kdump

[jcastill]

This change enables the RH plugin to display the content of /var/crash via the command 'ls', and adds a new option to capture the latest vmcores generated
in the last 24 hours, smaller than 2GB, as it's
done in the AzureDump class.

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[packit-as-a-service]

Congratulations! One of the builds has completed. 🍾

You can install the built RPMs by following these steps:

• sudo yum install -y dnf-plugins-core on RHEL 8
• sudo dnf install -y dnf-plugins-core on Fedora
• dnf copr enable packit/sosreport-sos-3612
• And now you can install the packages.

Please note that the RPMs should be used only in a testing environment.

[jcastill]

I've changed the option in the Azure plugin as well, because it was strange to have two different formats for the option. We haven't shipped the Azure kdump changes made some weeks ago yet, right? So no user has seen the option and we have still the room to change it.
That said, I was thinking on moving the option from get-vm-core to get-vmcore. It reads more naturally (we never asked for a vm-core in support, it was always vmcore) and the file itself is not hyphenated. What do you think?

I'm still working on merging Azure and RH plugins because they are almost the same, but that will have to be another PR.

[arif-ali]

I think the Azure bit was already changed by Jake

nevertheless, I think the Azure Linux folks have their own way of incorporating stuff, at least based on hat I saw a few months back, when they were trying to get 4.6.1 in. So, it could be that, when they added it here, they may of updated their RPMs