Remove obsolete Group tag

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

libebml.spec

@@ -3,7 +3,6 @@ Name:       libebml
 Version:    1.3.6
 Release:    2%{?dist}
 License:    LGPLv2+
-Group:      System Environment/Libraries
 URL:        https://www.matroska.org/
 Source:     https://dl.matroska.org/downloads/%{name}/%{name}-%{version}.tar.xz
 BuildRequires: cmake
@@ -17,7 +16,6 @@ pendant to XML.
 
 %package    devel
 Summary:    Development files for the Extensible Binary Meta Language library
-Group:      Development/Libraries
 Requires:   %{name}%{?_isa} = %{version}-%{release}
 Requires:   cmake-filesystem
 Requires:   pkgconfig