CI: install missing python3-django-filters

Signed-off-by: Rémi Duraffort <remi.duraffort@linaro.org>
10 jobs for master in 11 minutes and 59 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #58333
amd64
dispatcher/install/buster

00:05:14

passed #58331
amd64
dispatcher/install/stretch-backports

00:05:17

passed #58334
amd64
dispatcher/upgrade/buster

00:09:21

passed #58332
amd64
dispatcher/upgrade/stretch-backports

00:07:45

passed #58329
amd64
server/install/buster

00:05:28

passed #58327
amd64
server/install/stretch-backports

00:05:24

passed #58330
amd64
server/upgrade/buster

00:11:18

passed #58328
amd64
server/upgrade/stretch-backports

00:10:12

 
  Publish
skipped #58335
amd64
failure
passed #58336
amd64
success

00:00:40