Override of Hosttailer default image fails

[diogoasouza]

Describe the bug:
Hosttailer ignores the image set in spec.image.repository, it only works when you set containerOverrides.image for each fileTrailers.

Expected behaviour:
When setting spec.image.repository, Hosttailer should use that image in all containers if no containerOverrides is set, like EventTailer does.

Steps to reproduce the bug:

1. Create a new HostTailer resource populating spec.image

apiVersion: logging-extensions.banzaicloud.io/v1alpha1
kind: HostTailer
metadata: 
  name: cluster-system-log-test
spec: 
  image: 
    repository: docker-kube-registry.fake/fluent/fluent-bit
    tag: 3.1.8
  workloadMetaOverrides: 
    annotations: {}
    labels: {}
  fileTailers: 
    - disabled: false
      name: kubelet-log
      path: /var/lib/rancher/rke2/agent/logs/*.log
    - disabled: false
      name: containerd-log
      path: /var/lib/rancher/rke2/agent/containerd/*.log
    - name: kube-audit
      path: /var/log/kube-audit/audit-log.json
      disabled: false

2. Check the daemonSet created and look at the images used by each container

Environment details:

• Kubernetes version (e.g. v1.15.2): 1.31
• Cloud-provider/provisioner (e.g. AKS, GKE, EKS, PKE etc): K3s
• logging-operator version (e.g. 2.1.1): 5.2
• Install method (e.g. helm or static manifests): helm
• Logs from the misbehaving component (and any other relevant logs):
• Resource definition (possibly in YAML format) that caused the issue, without sensitive data:

/kind bug

[pepov]

I beleive this was a mistake in the original PR. Based on the code this should work for both file and systemd tailers:

apiVersion: logging-extensions.banzaicloud.io/v1alpha1
kind: HostTailer
metadata: 
  name: cluster-system-log-test
spec: 
  workloadMetaOverrides: 
    annotations: {}
    labels: {}
  fileTailers: 
    - disabled: false
      name: kubelet-log
      path: /var/lib/rancher/rke2/agent/logs/*.log
      image: 
        repository: docker-kube-registry.fake/fluent/fluent-bit
        tag: 3.1.8