Template activation: skip gutenberg_get_registered_block_templates query when no slugs are left to find (#72795)

Co-authored-by: ellatrix <ellatrix@git.wordpress.org>
Co-authored-by: Aljullu <aljullu@git.wordpress.org>
Co-authored-by: kmanijak <karolmanijak@git.wordpress.org>
Co-authored-by: bacoords <bacoords@git.wordpress.org>

Author: 4 people

backport-changelog/6.9/10432.md

@@ -1,3 +1,4 @@
 https://github.com/WordPress/wordpress-develop/pull/10432
 
-* https://github.com/WordPress/gutenberg/pull/72770
+* https://github.com/WordPress/gutenberg/pull/72770
+* https://github.com/WordPress/gutenberg/pull/72795

lib/compat/wordpress-6.9/template-activate.php

@@ -309,10 +309,12 @@ function ( $template ) {
 	}
 
 	// For any remaining slugs, use the static template.
-	$query     = array(
-		'slug__in' => $remaining_slugs,
-	);
-	$templates = array_merge( $templates, gutenberg_get_registered_block_templates( $query ) );
+	if ( ! empty( $remaining_slugs ) ) {
+		$query     = array(
+			'slug__in' => $remaining_slugs,
+		);
+		$templates = array_merge( $templates, gutenberg_get_registered_block_templates( $query ) );
+	}
 
 	if ( $specific_template && in_array( $specific_template, $remaining_slugs, true ) ) {
 		$templates = array_merge( $templates, get_block_templates( array( 'slug__in' => array( $specific_template ) ) ) );