[GH System tests] Downgrade Docker if the runner has docker v29.x.

[himani2411]

Description of changes

• Downgrade Docker if the runner has docker v29.x. Other wise skip the Downgrade step.
• Skip the Downgrade Docker so that we are aware of when to revert the workaround [GH System Test] Pinning kitchen-dokken in order to tackle upgrade of docker engine in GH runners #3124
• We do not block the PR merge on failure of AL2 and AL2023 system tests since they fail with CW installation or not availability of GLIBC ruby -> https://github.com/aws/aws-parallelcluster-cookbook/actions/runs/22190525744/job/64176702663

Tests

• System tests in this PR

References

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