[Liqoctl] interaction schema

[cheina97]

Description

This PR clarifies how liqoctl interacts with Liqo.

It adds liqoctl inside the connectivity requirements schema and a new schema in the liqoctl installation page.

[adamjensenbot]

Hi @cheina97. Thanks for your PR!

I am @adamjensenbot.
You can interact with me issuing a slash command in the first line of a comment.
Currently, I understand the following commands:

• /rebase: Rebase this PR onto the master branch (You can add the option test=true to launch the tests
  when the rebase operation is completed)
• /merge: Merge this PR into the master branch
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• /test Launch the E2E and Unit tests
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Make sure this PR appears in the liqo changelog, adding one of the following labels:

• kind/breaking: 💥 Breaking Change
• kind/feature: 🚀 New Feature
• kind/bug: 🐛 Bug Fix
• kind/cleanup: 🧹 Code Refactoring
• kind/docs: 📝 Documentation

[frisso]

This looks very good to me.
Minor comment: instead of the icon showing a person, we can use an icon showing a person behind a computer (e.g., https://uxwing.com/programmer-icon/), which makes clearer that we're referring to the programmer that is trying to get access to the cluster with Liqo.