use source URL returning a properly named tarball

Signed-off-by: Nils Philippsen <nils@tiptoe.de>

libsass.spec

@@ -5,7 +5,7 @@ Summary:        C/C++ port of the Sass CSS precompiler
 
 License:        MIT
 URL:            http://sass-lang.com/libsass
-Source0:        https://github.com/sass/libsass/archive/%{version}.tar.gz
+Source0:        https://github.com/sass/libsass/archive/%{version}/%{name}-%{version}.tar.gz
 
 BuildRequires:  automake
 BuildRequires:  autoconf
@@ -65,6 +65,9 @@ find $RPM_BUILD_ROOT -name '*.la' -exec rm -f {} ';'
 
 
 %changelog
+* Tue Nov 26 2019 Nils Philippsen <nils@tiptoe.de>
+- use source URL returning a properly named tarball
+
 * Tue Oct 01 2019 Aurelien Bompard <abompard@fedoraproject.org> - 3.6.1-1
 - Version 3.6.1