feat: add flag to disable to the memory swappiness

[soyji]

Hi, this is jiahaojz-onum smurf account, this issue closes https://github.com/containrrr/watchtower/issues/1060

I am running podman with crun and cgroupv2, default in systems like redhat

┌💁  jiahao-ji-zhou @ 💻  jiahao-ji-zhou-ThinkPad-E14-Gen-5 in 📁  watchtower on 🌿  feat/podman-compatibility → origin ⌀3 ✗
└❯ podman info | grep -i runtime -A3
  ociRuntime:
    name: crun
    package: crun_1.14.1-1_amd64
    path: /usr/bin/crun

┌💁  jiahao-ji-zhou @ 💻  jiahao-ji-zhou-ThinkPad-E14-Gen-5 in 📁  watchtower on 🌿  feat/podman-compatibility → origin ⌀3 ✗
└❯ podman info | grep cgroupVersion
  cgroupVersion: v2

The tests performed are for checking that watchtower works with podman. Those are executions with the flag:

Then the tests performed without the flag (the normal behaviour):

[apparle]

@simskij -- I'm also interested in this fix as it makes Nextcloud AIO (which uses watchtower under-the-hood) work with podman. I've also tested @soyji's change locally with podman and it works great.

It'll be great if you can review when you get a chance.

[WorkHardes]

+1 for release this

[nicholas-fedor]

@soyji Throw a PR my way and we can look at implementing it in my fork.