Allow to add additional credential-providers

**What I'd like:**
It looks like the [only supported credential-providers is ecr-credential-provider](https://bottlerocket.dev/en/os/1.20.x/api/settings/kubernetes/#credential-providers).

IIUC it would technically be possible to support additional credential-providers if we were able to deploy a credentials provider plugin in the image-credential-provider-bin-dir (/x86_64-bottlerocket-linux-gnu/sys-root/usr/libexec/kubernetes/kubelet/plugins?).

Then we would just have to declare it in `settings.kubernetes.credential-providers`.

**Any alternatives you've considered:**
We currently propagate an image pull secret and patch the pods using Kyverno policies instead.