SUSE has moved libncurses.so.5 to their legacy repository on SLE 15. This means that a default installation won't have this and tl-setup will fail to install it.
We don't currently use libncurses.so.5, but we still require it because of our requirement of LSB core libraries.
We've decided to drop this requirement. We won't change the documentation at this point though in order to keep it simple. However we will update tl-setup and our automatic tests.
tl-setup is now updated to no longer require libncurses.so.5. Our automatic tests did not need to be modified.
Verified that tl-setup no longer looks for libncurses.
When using build 6180 of ThinLinc on SLES 15 I first ensured that libncurses wasn't installed, then installed ThinLinc and ran tl-setup. tl-setup didn't care that it wasn't installed, and ThinLinc was setup and could run without problems.