net/htpdate: update to v1.3.7, support ssl (default), shift to github

• bugfix: wrong default portnumber for proxy was used
• bugfix: https://bugs.launchpad.net/ubuntu/+source/htpdate/+bug/1850740

With hat: ports-sec team

(cherry picked from commit 687a1b3d4995b3b98abdcdcfd1cbef25e1b24f6b)