Docs: add more nodes for --cloud-nodes

[adamzhoul]

What type of PR is this?

/kind documentation

What this PR does / why we need it:

two points here:

1. update description about convert.

this update is for better understating.
the command below is to convert with one node as a cloud node. same as the logic thought.

2. add a note, how to use "," to add more nodes for --cloud-nodes params

this is useful when we deploy our openYurt cluster.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

other Note

[openyurt-bot]

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In response to this:

What type of PR is this?

/kind documentation

What this PR does / why we need it:

two points here:

1. update description about convert.

this update is for better understating.
the command below is to convert with one node as a cloud node. same as the logic thought.

2. add a note, how to use "," to add more nodes for --cloud-nodes params

this is useful when we deploy our openYurt cluster.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

other Note

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[openyurt-bot]

Welcome @adamzhoul! It looks like this is your first PR to openyurtio/openyurt 🎉

[adamzhoul]

/assign @yixingjia
please have a look.

[rambohe-ch]

@adamzhoul Very appreciate you for improving the document of OpenYurt. and welcome you to apply for OpenYurt community member. you can get apply example here: openyurtio/community#23

[adamzhoul]

@adamzhoul Very appreciate you for improving the document of OpenYurt. and welcome you to apply for OpenYurt community member. you can get apply example here: openyurtio/community#23

@rambohe-ch thanks for your inviting. will do it soon.

[rambohe-ch]

/lgtm
/approve

[openyurt-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: adamzhoul, rambohe-ch

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