python-crossbar: drop Python 2 support

Upstream is now Python 3 only.

Quoting the maintainer [1]: "the last version of crossbar with python 2
support: pip install crossbar==18.4.1".

[1] https://github.com/crossbario/crossbar/issues/1332

Signed-off-by: Ricardo Martincoski <ricardo.martincoski@gmail.com>
Cc: Asaf Kahlon <asafka7@gmail.com>
Cc: Mauro Condarelli <mc5686@mclink.it>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
1 file changed