Block Hooks: Apply block hooks to plugin-registered templates

[Adi-ty]

This PR fixes an inconsistency where block hooks were not being applied to templates registered by plugins using register_block_template().

Trac ticket: https://core.trac.wordpress.org/ticket/63808

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This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[github-actions]

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[github-actions]

The following accounts have interacted with this PR and/or linked issues. I will continue to update these lists as activity occurs. You can also manually ask me to refresh this list by adding the props-bot label.

Core Committers: Use this line as a base for the props when committing in SVN:

Props iamadisingh, aljullu, bernhard-reiter.

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[Aljullu]

Thanks for working on this, @Adi-ty! I tested with the testing steps from WordPress/gutenberg#71139 and I can confirm that:

1. In the frontend, the template from the plugin correctly displays the hooks:

Before	After

2. When making a request to /wp-json/wp/v2/templates/twentytwentyfive//plugin-template, the template in the response now has the hooks applied to the content.

Before	After

3. That is not a problem when accessing the template in the site editor (ie: /wp-admin/site-editor.php?canvas=edit&p=%2Fwp_template%2Ftwentytwentyfive%2F%2Fplugin-template). Hooks are still rendered only once.

I'm approving from my side, but I don't have permisions in WP core. @ockham wondering if you (or somebody you know) can help us move this forward?

[Adi-ty]

Thanks for working on this, @Adi-ty! I tested with the testing steps from WordPress/gutenberg#71139 and I can confirm that:

1. In the frontend, the template from the plugin correctly displays the hooks:

Before After

2. When making a request to /wp-json/wp/v2/templates/twentytwentyfive//plugin-template, the template in the response now has the hooks applied to the content.

Before After

3. That is not a problem when accessing the template in the site editor (ie: /wp-admin/site-editor.php?canvas=edit&p=%2Fwp_template%2Ftwentytwentyfive%2F%2Fplugin-template). Hooks are still rendered only once.

I'm approving from my side, but I don't have permisions in WP core. @ockham wondering if you (or somebody you know) can help us move this forward?

Thanks for testing and confirming the changes. Hopefully we can get this moved forward soon.

[ockham]

Thank you both! I'll go ahead and commit this 👍

[github-actions]

A commit was made that fixes the Trac ticket referenced in the description of this pull request.

SVN changeset: 60688
GitHub commit: 7158d9f

This PR will be closed, but please confirm the accuracy of this and reopen if there is more work to be done.