fix(homepage-articles): use map_deep to construct articles_rest_url and resolve PHP 8.1 warnings

[mreishus]

All Submissions:

• Have you followed the Newspack Contributing guideline?
• Does your code follow the WordPress' coding standards and VIP Go coding standards?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changes proposed in this Pull Request:

The newspack_blocks_render_block_homepage_articles() function does this:

	$articles_rest_url = add_query_arg(
		array_merge(
			array_map(
				function( $attribute ) {
					return false === $attribute ? '0' : $attribute;
				},
				$attributes
			),
			[
				'page' => 2,
			]
		),
		rest_url( '/newspack-blocks/v1/articles' )
	);

However, array_map only works one level deep into arrays. When nested arrays are passed in, this code converts the sub array's value to the string "Array" which generates a warning:

[30-Jan-2024 18:51:17 UTC] Warning: Array to string conversion in (...)/wp-content/plugins/editing-toolkit-plugin/prod/newspack-blocks/synced-newspack-blocks/blocks/homepage-articles/view.php on line 160 

Fix: Use map_deep() from WordPress instead ( https://developer.wordpress.org/reference/functions/map_deep/ ).

Example of one of the values passed in that causes this warning, before and after the mapping:

    [before] => Array                                                                                                       
        (                                                                                                                   
            [action] => hide                                                                                                
            [rules] => Array                                                                                                
                (                                                                                                           
                    [0] => Array                                                                                            
                        (                                                                                                   
                            [major] => category                                                                             
                            [minor] => 22388                                                                                
                        )                                                                                                   
                                                                                                                            
                )                                                                                                           
                                                                                                                            
            [match_all] => 0                                                                                                
        )                                                                                                                   

    [after] => Array
        (
            [action] => hide
            [rules] => Array
            [match_all] => 0
        )

Notice that $v['rules'] is transformed from an actual array to the string Array.

How to test the changes in this Pull Request:

1. See D136469-code for an example of this applied to WPCOM, with specific sites listed that exhibit the warning and testing directions.

Other information:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes, as applicable?
• Have you successfully ran tests with your changes locally?

[adekbadek]

Thanks!

[matticbot]

🎉 This PR is included in version 3.0.0-epic-test-epic-release-flow-raz.1 🎉

The release is available on:

• npm package (@epic/test-epic-release-flow-raz dist-tag)
• GitHub release

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[matticbot]

🎉 This PR is included in version 3.0.0-epic-ras-acc.1 🎉

The release is available on:

• npm package (@epic/ras-acc dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[matticbot]

🎉 This PR is included in version 3.0.0-alpha.1 🎉

The release is available on:

• npm package (@alpha dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[matticbot]

🎉 This PR is included in version 3.0.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀