chore: prepare for WordPress 5.4 (#42g9wx)

Author: matzeeable

README.md

@@ -3,7 +3,7 @@ Contributors: mguenter, TigrouMeow
 Tags: lightroom, image, gallery, media, photo, export, management, admin, sync, synchronization, real media library, add-on, wplr-extension
 Requires at least: 4.4
 Requires PHP: 5.4.0
-Tested up to: 5.0.1
+Tested up to: 5.4
 Stable tag: trunk
 
 Displays the hierarchy of folders and collections nicely on the left side of your Media Library by syncing with the Real Media Library plugin.
@@ -66,4 +66,4 @@ The extension creates shortcuts only when necessary. That means a shortcut is cr
 
 == Screenshots ==
 1. The Lightroom publish services...
-2. ... is automatically synchronized with your Media Library
+2. ... is automatically synchronized with your Media Library