Update install ansible docs

[jimyag]

What type of PR is this?

/kind bug

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #11465 #11418

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

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Hi @jimyag. Thanks for your PR.

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[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: jimyag
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[mzaian]

/ok-to-test

[VannTen]

You don't need this if you don't use the dynamic inventory, please make this clear

[jimyag]

I did what

kubespray/README.md

Lines 29 to 33 in 1798989

	# Update Ansible inventory file with inventory builder
	declare -a IPS=(10.10.1.3 10.10.1.4 10.10.1.5)
	CONFIG_FILE=inventory/mycluster/hosts.yaml python3 contrib/inventory_builder/inventory.py ${IPS[@]}
	# Review and change parameters under ``inventory/mycluster/group_vars``

describes.
Executing CONFIG_FILE=inventory/z2air/hosts.yaml python contrib/inventory_builder/inventory.py ${IPS[@]} gives the error Not a module named ruamel.

Looking through the issue, I found a solution that requires the ruamel.yaml module to be installed.

A number of people have had the same problem, and I think it's necessary to add the relevant description somewhere correct, but I'm not sure I'm adding it in the right place.

[VannTen]

Then this line should be in the README just before using the inventory.py script, since it's not for installing ansible, but just to run the script.