Merge pull request #6880 from daniviga/rpm-f27

Update RPM spec since GRASS 7.4 has been backported to F27

Author: m-kuhn

rpm/qgis.spec.template

@@ -12,7 +12,7 @@
 %define builddate %(date '+%a %b %d %Y')
 %endif
 
-%if 0%{?fedora} >= 28
+%if 0%{?fedora} >= 27
 %define grass grass74
 %else
 %define grass grass72