README.md - HTTPS Link for GNU.org

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README.md

@@ -35,4 +35,4 @@ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 See the GNU Lesser General Public License for more details.
 
 You should have received a copy of the GNU Lesser General Public License
-along with BOINC.  If not, see <http://www.gnu.org/licenses/>.
+along with BOINC.  If not, see <https://www.gnu.org/licenses/>.