Convert kubeadm.yaml.erb to jinja format

[Bart Wensley]

Brief Description
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Review https://review.opendev.org/#/c/703911 moved the kubeadm.yaml.erb template from puppet to ansible, but left the file in the erb format. This file should be converted to the recommended ansible template format (jinja), which will allow many ugly sed commands to be removed from the playbooks and make the file easier to maintain in the future.

Severity
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Minor

Steps to Reproduce
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N/A

Expected Behavior
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N/A

Actual Behavior
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N/A

Reproducibility
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N/A

System Configuration
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N/A

Branch/Pull Time/Commit
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See review mentioned above.

Last Pass
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N/A

Timestamp/Logs
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Test Activity
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N/A

Workaround
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N/A

[Ghada Khalil (gkhalil)]

Low priority - code cleanup. Would be nice to fix, but doesn't gate any stx release.

[Ghada Khalil (gkhalil)]

Assigning to David Sullivan since he's the author of: https://review.opendev.org/#/c/703911 and this is a follow-up for that commit

[John Kung (john-kung)]

This is resolved as ansible-playbooks commit https://opendev.org/starlingx/ansible-playbooks/commit/3ccadeab0b34dc082ba62a580eb4fe10d24a0540 converts to kubeadm.yaml.erb to kubeadm.yaml.j2 jinja format.