Block Bindings: Expose sources in the editor settings to consume them in the client

[santosguillamot]

Add a new property to the editor settings to expose the block bindings sources registered in the server. This allows to reuse some of its properties like label and uses_context without having to replicate that in JavaScript.

It makes some block bindings editor functionalities work by default, improving the user experience, and it simplifies how sources are registered in the client.

Originally explored in this other pull request: ​https://github.com/WordPress/wordpress-develop/pull/6456

## What?

It adds a new property to the editor settings to expose the block bindings sources registered in the server. This allows to reuse some of its properties like label and uses_context without having to replicate that in JavaScript.

## Why?

It makes some block bindings editor functionalities work by default, improving the user experience, and it simplifies how sources are registered in the client.

## How?

Add a new property including all the registered sources while the editor settings are being initialized.

Trac ticket: https://core.trac.wordpress.org/ticket/61641

I’m wondering if we can update an existing unit test to validate the setting is correctly propagated to the editor

I’m wondering if we can update an existing unit test to validate the setting is correctly propagated to the editor

I have just added this new unit test to check that the registered sources are properly added to the editor settings: ​link.

[cbravobernal]

In 58798:

Block Bindings: Adds sources in the editor settings to consume them in the client

Adds a new property blockBindingsSources to the editor settings to expose the block bindings sources registered in the server.

Props santosguillamot, cbravobernal, gziolo, artemiosans.
Fixes #61641.

Completed with my first commit to Core in https://core.trac.wordpress.org/changeset/58798

[czapla]

In 58799:

Tests: Removes the obsolete Block Binding unregistration

Follow-up to [58798].
Props santosguillamot, cbravobernal, gziolo.
See #61641.

Thanks for committing this early in the 6.7 cycle ❤️