Actions: Add echo workflow command

[Simran-B]

Why:

Closes #7868

What's being changed:

Add a section about the echo workflow command (::echo::on and ::echo::off) provided by actions toolkit: https://github.com/actions/toolkit/blob/main/docs/commands.md#command-echoing

Check off the following:

• I have reviewed my changes in staging (look for "Automatically generated comment" and click Modified to view your latest changes).
• For content changes, I have completed the self-review checklist.

[github-actions]

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This comment is automatically generated and will be overwritten every time changes are committed to this branch.

The table contains an overview of files in the content directory that have been changed in this pull request. It's provided to make it easy to review your changes on the staging site. Please note that changes to the data directory will not show up in this table.

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Content directory changes

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Source	Staging	Production	What Changed
content/actions/learn-github-actions/workflow-commands-for-github-actions.md	Modified	Original

[ramyaparimi]

@Simran-B
Thanks so much for opening a PR! I'll get this triaged for review ⚡

[lucascosti]

Thanks a lot for this, @Simran-B! I've pushed a few edits in dccd754, so I think this is good to merge

[github-actions]

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