Logging: Prevent fatal type error when submitting empty search (#41847)

plugins/woocommerce/changelog/fix-log-search-fatal

@@ -0,0 +1,4 @@
+Significance: patch
+Type: fix
+
+Prevent fatal error when submitting an empty search query on the log files screen.

plugins/woocommerce/src/Internal/Admin/Logging/FileV2/FileController.php

@@ -421,7 +421,7 @@ class FileController {
 	 */
 	public function search_within_files( string $search, array $args = array(), array $file_args = array(), bool $count_only = false ) {
 		if ( '' === $search ) {
-			return array();
+			return $count_only ? 0 : array();
 		}
 
 		$search = esc_html( $search );