Added example for getSaveElement

[CWBudde]

What?

Added an example for getSaveElement, which was previously missing.

Why?

The documentation was quite limited at this place.

How?

It might not be the best example, but it gives a basic hint on how to use getSaveElement

Testing Instructions

Setup a basic block filter plugin and insert the above code.

[github-actions]

👋 Thanks for your first Pull Request and for helping build the future of Gutenberg and WordPress, @CWBudde! In case you missed it, we'd love to have you join us in our Slack community, where we hold regularly weekly meetings open to anyone to coordinate with each other.

If you want to learn more about WordPress development in general, check out the Core Handbook full of helpful information.

[gziolo]

Thank you for extending this section in the documentation.

[github-actions]

Congratulations on your first merged pull request, @CWBudde! We'd like to credit you for your contribution in the post announcing the next WordPress release, but we can't find a WordPress.org profile associated with your GitHub account. When you have a moment, visit the following URL and click "link your GitHub account" under "GitHub Username" to link your accounts:

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Kudos!