openSUSE: 2020:1192-1 Important Security Fix for Claws-Mail Update

This update for claws-mail fixes the following issues:

- Update to 3.17.6:

* It is now possible to 'Inherit Folder properties and processing rules

from parent folder' when creating new folders with the move message and

copy message dialogues.

* A Phishing warning is now shown when copying a phishing URL, (in

addition to clicking a phishing URL).

* The progress window when importing an mbox file is now more responsive.

* A warning dialogue is shown if the selected privacy system is 'None'

and automatic signing amd/or encrypting is enabled.

* Python plugin: pkgconfig is now used to check for python2. This enables

the Python plugin (which uses python2) to be built on newer systems

which have both python2 and python3.

- CVE-2020-15917: Fixed an improper handling of suffix data after STARTTLS

is mishandled (boo#1174457).

This update was imported from the openSUSE:Leap:15.2:Update update project.