Revert FilePicker to 5.2.5

Hopefully fix #1572, #1563, #1562

Author: FeodorFitsner

package/pubspec.yaml

@@ -32,7 +32,7 @@ dependencies:
   flutter_highlight: ^0.7.0
   highlight: ^0.7.0
   markdown: ^7.0.0
-  file_picker: ^5.3.0
+  file_picker: ^5.2.5
   shared_preferences: ^2.0.15
   flutter_svg: ^1.1.6
   window_to_front: ^0.0.3