When using a resource directory with a desktop-file and a spec-file.
The resulting RPM file will contain the desktop file, but its filename is
wrong. It is adding the application name twice.

Instead of "test-application.desktop" the RPM contains
"test-application-test-application.desktop".

I created a test application project on GitHub to demonstrate this problem.
https://github.com/DJViking/test-application

Running the gradle task createPackage will create an RPM with the desktop
file.
~> export JAVA_HOME=/usr/java/jdk-14
~> ./gradlew createPackage