Build-require python3-devel for tests
Make target for tests is created only if python is installed and that
is controlled by %__python3 devel macro in spec file that exists only
if python3-devel package is installed. Otherwise the test fails if
generating documentation is disabled:
Executing(%check): /bin/sh -e /var/tmp/rpm-tmp.O8YL29
+ umask 022
+ cd /builddir/build/BUILD
+ cd jsoncpp-1.8.3
+ /usr/bin/make -O -j6 -C x86_64-redhat-linux-gnu jsoncpp_check
make: *** No rule to make target 'jsoncpp_check'. Stop.