Fix: Missing CSS when do_blocks is ran early

[tomusborne]

alternative to #682

#682 works but has an issue where CSS (singular and block-specific) is duplicated when using block themes.

This method works by using wp_enqueue_scripts and wp_add_inline_style for our inline style. This works because wp_enqueue_scripts fires before wp_head which is where Slim SEO (in this case) is calling do_blocks.

We also have to check $block_ids within the generateblocks_get_dynamic_css function to prevent duplicate CSS in block themes.

Not sure if this is the best solution.

[JeanPaiva]

I could not find any CSS duplication with GP/2022 block theme or widget areas, and the original issue is still fixed.