Coding Standards: Remove unreachable return in _get_block_template_file().

This commit removes an unreachable `return` statement, as the function will bail early if  `$template_type` is not a `wp_template` or `wp_template_part`.

For the same reason, the second `if` conditional was also redundant and is now removed.

Follow-up to [52062].

Props justlevine.
See #63268.

git-svn-id: https://develop.svn.wordpress.org/trunk@60328 602fd350-edb4-49c9-b593-d223f7449a82

Author: SergeyBiryukov

src/wp-includes/block-template-utils.php

@@ -344,11 +344,8 @@ function _get_block_template_file( $template_type, $slug ) {
 				return _add_block_template_part_area_info( $new_template_item );
 			}
 
-			if ( 'wp_template' === $template_type ) {
-				return _add_block_template_info( $new_template_item );
-			}
-
-			return $new_template_item;
+			// If it's not a `wp_template_part`, it must be a `wp_template`.
+			return _add_block_template_info( $new_template_item );
 		}
 	}