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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[github-actions]

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Props petitphp, mukesh27.

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[mukeshpanchal27]

Does this change will impact on performance?

[petitphp]

Are we talking about server (PHP) or frontend (resources loading) performances ?

[mukeshpanchal27]

Frontend.

[petitphp]

Currently, if a block style is register with a style_handle the CSS file is not included on the frontend. This PR fix that, so it's possible that it'll have an impact in terms of performance.

We could try and mitigate this by dynamically adding a path extra data to the dependency to let WordPress inline the style if it's below the threshold.

[github-actions]

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