[Scaling] Removing usage of cfn-init for compute fleet

[himani2411]

Description of changes

• Removing usage of cfn-init for compute fleet
• Using write_files in user_data.sh of compute fleet

Dependent on cookbook PR aws/aws-parallelcluster-cookbook#2875

Tests

test-suites:
  update:
    test_update.py::test_dynamic_file_systems_update:
      dimensions:
        - regions: [ "us-east-2" ]
          instances: {{ common.INSTANCES_DEFAULT_X86 }}
          oss: [ "alinux2023" ]
          schedulers: [ "slurm" ]
    test_update.py::test_update_slurm:
      dimensions:
        - regions: ["eu-central-1"]
          instances: {{ common.INSTANCES_DEFAULT_X86 }}
          oss: ["rocky8"]
    test_update.py::test_update_compute_ami:
      dimensions:
        - regions: ["eu-west-1"]
          instances: {{ common.INSTANCES_DEFAULT_X86 }}
          oss: ["rocky9"]
    test_update.py::test_update_instance_list:
      dimensions:
        - regions: ["ap-south-1"]
          instances: {{ common.INSTANCES_DEFAULT_X86 }}
          oss: ["ubuntu2004"]
          schedulers: ["slurm"]
    test_update.py::test_queue_parameters_update:
      dimensions:
        - regions: [ "ap-south-1" ]
          instances: {{ common.INSTANCES_DEFAULT_X86 }}
          oss: ["alinux2"]
          schedulers: [ "slurm" ]
    test_update.py::test_dynamic_file_systems_update_rollback:
      dimensions:
        - regions: [ "us-east-2" ]
          instances: {{ common.INSTANCES_DEFAULT_X86 }}
          oss: [ "rhel8" ]
          schedulers: [ "slurm" ]

References

• Link to impacted open issues.
• Link to related PRs in other packages (i.e. cookbook, node).
• Link to documentation useful to understand the changes.

Checklist

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