bug#29258: web client fails on https

[Amirouche Boubekki]

GNU Guile 2.2.2
Copyright (C) 1995-2017 Free Software Foundation, Inc.

Guile comes with ABSOLUTELY NO WARRANTY; for details type `,show w'.
This program is free software, and you are welcome to redistribute it
under certain conditions; type `,show c' for details.

Enter `,help' for help.
scheme@(guile-user)> (use-modules (web client))
scheme@(guile-user)> (http-get "https://www.gnu.org";)
ERROR: In procedure get-bytevector-n:
ERROR: Throw to key `gnutls-error' with args `(#<gnutls-error-enum La 
connexion TLS n’a pas été terminée correctement.> 
read_from_session_record_port)'.

Entering a new prompt.  Type `,bt' for a backtrace or `,q' to continue.
scheme@(guile-user) [1]>

scheme@(guile-user)> (use-modules (gnutls))
scheme@(guile-user)> (gnutls-version)
$1 = "3.5.13"