Remove obsolete Group tag

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

libchewing.spec

@@ -10,7 +10,6 @@ Release:        9%{?dist}
 Summary:        Intelligent phonetic input method library for Traditional Chinese
 Summary(zh_TW): %{name_zh_TW}
 
-Group:          System Environment/Libraries
 License:        LGPLv2+
 URL:            http://chewing.csie.net/
 Source0:        https://github.com/chewing/%{name}/archive/v%{version}.tar.gz
@@ -38,7 +37,6 @@ input method that is useful for inputting Mandarin Chinese.
 %package -n %{name}-devel
 Summary:        Development files for libchewing
 Summary(zh_TW): %{name_zh_TW}開發者套件
-Group:          Development/Libraries
 Requires:       %{name}%{?_isa} = %{version}-%{release}
 
 %description -n %{name}-devel
@@ -53,7 +51,6 @@ library.
 %package -n python2-%{name}
 Summary:        Python binding for libchewing
 Summary(zh_TW): %{name_zh_TW} python 綁定
-Group:          Development/Libraries
 BuildRequires:  python2-devel
 Requires:       %{name}%{?_isa} = %{version}-%{release}
 Requires:       python2