Site Logo: Correctly reset the site icon

[akasunil]

What?

If the logo image is reset or the site logo option "Use as site icon" is toggled off, the site icon is still used in the navigation sidebar in the site editor as per issue 39922. this pull request consist fix for site icon when it logo reset or "use as site icon" option is unchecked.

Fixes #39922.

Testing Instructions

Please follow step by step instructions to test this PR.

1. Upload a site logo.
2. Enable it as the site icon, save.
3. Refresh and see that the site icon replaces the WordPress logo in the navigation sidebar.
4. Disable the "Use as site icon" option, save.
5. See that the site icon still replaces the WP logo.
6. Reset the site logo image from the block toolbar, save.
7. See that the site icon still replaces the WP logo.

[github-actions]

👋 Thanks for your first Pull Request and for helping build the future of Gutenberg and WordPress, @sunil25393! 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.

[Mamaduka]

Thanks for contributing, @sunil25393. I left a few suggestions that would be nice to include in this PR.

[paaljoachim]

Thank you, thank you and again another thank you!
Some time ago I added a custom site icon (Twenty Twenty Two). Which replaced the W logo seen in the top left corner.
Even though I turned off the "Use as site icon" toggle for the Site Logo the custom icon was still seen. I was not able to get the W logo back.

Testing your PR and Toggling off the "Use as site icon" for the Site Logo the W returned.

This works well for me!

I thought I would inform both of you about this PR.
@annezazu @kjellr

[paaljoachim]

Feature fix works well!

[github-actions]

Congratulations on your first merged pull request, @sunil25393! 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:

https://profiles.wordpress.org/me/profile/edit/

And if you don't have a WordPress.org account, you can create one on this page:

https://login.wordpress.org/register

Kudos!

[akasunil]

I have linked my github account to my wordpress profile.
https://profiles.wordpress.org/sunil25393/

Thank you.

[Mamaduka]

Thanks, @sunil25393, and congrats on the first contribution 🎉