Remove obsolete Group tag

References: https://fedoraproject.org/wiki/Changes/Remove_Group_Tag

libXres.spec

@@ -7,7 +7,6 @@ Name: libXres
 Version: 1.2.0
 Release: 5%{?gitdate:.%{gitdate}git%{gitversion}}%{?dist}
 License: MIT
-Group: System Environment/Libraries
 URL: http://www.x.org
 
 %if 0%{?gitdate}
@@ -31,7 +30,6 @@ the X server about its usage of various resources.
 
 %package devel
 Summary: Development files for %{name}
-Group: Development/Libraries
 Requires: %{name} = %{version}-%{release}
 
 %description devel