Update Fleet to v0.9.0-rc.4

[rancherbot]

Update Fleet to v0.9.0-rc.4

Changelog: https://github.com/rancher/fleet/releases/tag/v0.9.0-rc.4

[github-actions]

Validation steps

• Ensure all container images have repository and tag on the same level to ensure that all container images are included in rancher-images.txt which are used by airgap customers.

  Ex:- 
    longhorn-controller:
      repository: rancher/hardened-sriov-cni
      tag: v2.6.3-build20230913
  

• Add a 👍 (thumbs up) reaction to this comment once done. CI won't pass without this reaction to the github-action bot's latest validation comment. The thumbs up reaction must be from the PR's author.
• Approve the PR to run the CI check.