BUG #16305: Application Stack Builder downloads MacOS JDBC binary

The following bug has been logged on the website:

Bug reference:      16305
Logged by:          maegawa
Email address:      y.maegawa.yc@future.co.jp
PostgreSQL version: 12.2
Operating system:   Windows10 October 2018 Update Ver.1809
Description:

I tried to install pgJDBCv42.2.5-3 using StackBuilder on Windows 10, but the
installation failed.

The downloaded file was named "edb_pgjdbc.exe", but when I unzipped it, it
contained 
"pgjdbc-42.2.5-3-osx.app\Contents\MacOS"
"pgjdbc-42.2.5-3-osx.app\Contents\Info.plist" and the other.

StackBuilder is version 4.1.0.