[doc] Use https for www.gnu.org (doc/include/gpl_v3.texi)

[Gerald Pfeifer]

Applied.

Gerald

2019-07-28  Gerald Pfeifer  <gerald@pfeifer.com>

	* doc/include/gpl_v3.texi (Copying): Use https for www.gnu.org.

Index: doc/include/gpl_v3.texi
===================================================================
--- doc/include/gpl_v3.texi	(revision 273850)
+++ doc/include/gpl_v3.texi	(working copy)
@@ -729,5 +729,5 @@ program into proprietary programs.  If your progra
 library, you may consider it more useful to permit linking proprietary
 applications with the library.  If this is what you want to do, use
 the GNU Lesser General Public License instead of this License.  But
-first, please read @url{http://www.gnu.org/philosophy/why-not-lgpl.html}.
+first, please read @url{https://www.gnu.org/philosophy/why-not-lgpl.html}.
 @c man end