Description of problem:

When I ran sudo dnf system-upgrade download --refresh --releasever=29
from my fully updated F28 installation with updates-testing enabled,
I got the following errors involving nmap

...
Problem 2: package nmap-frontend-2:7.60-12.fc28.noarch requires nmap = 2:7.60, but none of the providers can be installed
  - nmap-2:7.60-12.fc28.i686 does not belong to a distupgrade repository
  - problem with installed package nmap-frontend-2:7.60-12.fc28.noarch
...
Problem 8: package nmap-2:7.60-12.fc28.i686 requires nmap-ncat = 2:7.60-12.fc28, but none of the providers can be installed
  - package nmap-ndiff-2:7.60-12.fc28.noarch requires nmap = 2:7.60, but none of the providers can be installed
  - nmap-ncat-2:7.60-12.fc28.i686 does not belong to a distupgrade repository
  - problem with installed package nmap-ndiff-2:7.60-12.fc28.noarch

The nmap changelog includes the following
* Thu Apr 19 2018 Pavel Zhukov <pzhukov> - 2:7.70-2 - Do not build zenmap and ndiff because of python2 deprecation 

Adding the following lines to nmap.spec for F29 and rebuilding the nmap packages might resolve the errors above:
Obsoletes: nmap-frontend
Obsoletes: nmap-ndiff

Version-Release number of selected component (if applicable):
nmap-2:7.60-12.fc28.i686

How reproducible:
Always


Steps to Reproduce:
1. sudo dnf upgrade --refresh --enablerepo=testing
2. sudo dnf system-upgrade download --refresh --releasever=29
3.

Actual results:
dnf system-upgrade errors involving nmap

Expected results:
no dnf errors

Additional info: