Jetpack Autoupdates: Removed php warning (#9246)

* Jetpack Autoupdates: Removed php warning

PHP Warning: Non numeric value encountered.
Fixes typo

* more fixes

class.jetpack-autoupdate.php

@@ -44,7 +44,7 @@ public function autoupdate_translation( $update, $item ) {
 		if ( Jetpack_Options::get_option( 'autoupdate_translations', false ) ) {
 			return true;
 		}
-		
+
 		// Themes
 		$autoupdate_themes_translations = Jetpack_Options::get_option( 'autoupdate_themes_translations', array() );
 		$autoupdate_theme_list          = Jetpack_Options::get_option( 'autoupdate_themes', array() );
@@ -64,7 +64,7 @@ public function autoupdate_translation( $update, $item ) {
 		       || in_array( $item->slug, $autoupdate_theme_list ) )
 		     && 'theme' === $item->type
 		) {
-			$this->expect( $item->type + ':' + $item->slug, 'translation' );
+			$this->expect( $item->type . ':' . $item->slug, 'translation' );
 
 			return true;
 		}
@@ -78,7 +78,7 @@ public function autoupdate_translation( $update, $item ) {
 		if ( in_array( $item->slug, $plugin_slugs )
 		     && 'plugin' === $item->type
 		) {
-			$this->expect( $item->type + ':' + $item->slug, 'translation' );
+			$this->expect( $item->type . ':' . $item->slug, 'translation' );
 			return true;
 		}
 
@@ -220,7 +220,7 @@ private function get_successful_updates( $type ) {
 						$successful_updates[] = $result->item->theme;
 						break;
 					case 'translation':
-						$successful_updates[] = $result->item->type + ':' + $result->item->slug;
+						$successful_updates[] = $result->item->type . ':' . $result->item->slug;
 						break;
 				}
 			}