Update nodes in etc hosts after cluster scale

[zhan9san]

What type of PR is this?

/kind bug

What this PR does / why we need it:

Add new nodes into /etc/hosts of current nodes after cluster scale with scale.yml.

Which issue(s) this PR fixes:

Fixes #9817

Special notes for your reviewer:

Combine Hosts | create list from inventory and Hosts | populate inventory into hosts file into one block with one condition, so if populate_inventory_to_hosts_file is false, there is no need to run Hosts | create list from inventory.

Combine the localhost entries tasks into one block and add a variable populate_localhost_entries_to_hosts_file as a condition.

It will save some time, Respect #9279.

The ssl certificate has been generated in dns_early stage.
The setup task is a time-consuming task, so there is no need to update ansible_fqdn in dns_late stage.

Does this PR introduce a user-facing change?:

Update nodes in etc hosts after cluster scale

[k8s-ci-robot]

Hi @zhan9san. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[zhan9san]

cc @yankay

[yankay]

Thanks @zhan9san
/ok-to-test

[liupeng0518]

/lgtm

[oomichi]

Thanks for doing this.

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: oomichi, zhan9san

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