Block Variation Picker: adds support to declarated icon with src

[gigitux]

What?

This PR adds the support of a declared icon with src to the Block Variation Picker.

Why?

This avoids the crash of the Block Variation Picker when a variation has a declared icon with src. Fixes #46372.

How?

Testing Instructions

1. Create a Query Loop variation that has a declared icon with src (you can use this code).
2. Add the Query Loop block.
3. Click Start Blank.
4. Be sure the Block Variation Picker doesn't crash.

Screenshots or screencast

Screen.Capture.on.2022-12-07.at.17-58-27.mp4

[github-actions]

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

[jorgefilipecosta]

Most code guards against icon being undefined using "variation.icon && variation.icon.src ? variation.icon.src : variation.icon". I guess we can follow a similar approach but other that the change looks good and can be merged after the update.

[gigitux]

@jorgefilipecosta Thanks for the review! I updated the check!

[Aljullu]

@gigitux given that this PR was approved and you did the change, should we go ahead and merge?

[gigitux]

@gigitux given that this PR was approved and you did the change, should we go ahead and merge?

For me, it makes sense. Unfortunately, I don't have permission to merge the PR (I think that @ellatrix must approve the PR).

cc @jorgefilipecosta