Editor: Add test for context setting in Comment Template block.

Test that `commentId` context is correctly set and made available by the Comment Template block to the `render_block_context` filter (at priority 2 and higher), and to the `render_block` filter (important when programmatically inserting child blocks into the Comment Template block).

Furthermore, test that child blocks inserted via the `render_block_data` filter are retained and thus present at `render_block` filter stage.

Props andrewserong, ramonopoly, peterwilsoncc, costdev, mukesh27, flixos90.
Fixes #58839.
Built from https://develop.svn.wordpress.org/trunk@56262


git-svn-id: http://core.svn.wordpress.org/trunk@55774 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.3-beta4-56261';
+$wp_version = '6.3-beta4-56262';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.