Script Loader: Fix missing block style loaded with `style_handle`

[petitphp]

Fix missing block style loaded with style_handle.

It's possible to register a block style with a handle instead of an inline style. In that case and when wp_should_load_separate_core_block_assets() is true, the current code will rely on the render_block filter to detect if the block is used on the page and the block style need to be enqueued.

This doesn't work as expected, since the function is called in enqueue_block_assets after the render_block filter has run.

This PR add a new function hooked to wp_loaded to fix the issue.

Trac ticket: https://core.trac.wordpress.org/ticket/55184

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[kyle-charlton]

Is there any update on this? I would love to see this fixed soon so I can start including my block style variations in their own stylesheets.