Upgrade rocky9 version in createami to 9.4

[hgreebe]

Description of changes

• Upgrade rocky9 version in createami to 9.4
• When using a rocky9.3 base image instead of a rocky9.4 base image, the lustre client will not work unless we update the kernel, which caused build-image to fail

Tests

• Ran the following integ test:

test-suites:
  createami:
    test_createami.py::test_build_image:
      dimensions:
        - instances: ["c5.xlarge"]
          oss: ["rocky9"]
          regions: ["us-east-1"]
          schedulers: [ "slurm" ]

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