docker: modernisation and fixes:

- fix geckodriver version used following `backend-dev-e2e` base image update
- use Prosody image `prosodyim/prosody:0.12` instead of a deprecated one
- update `pubsub` image with base image update and use of new repos names

docker/pubsub/entrypoint.sh

@@ -11,7 +11,7 @@ until psql -c "select 1" > /dev/null 2>&1 || [ $RETRIES -eq 0 ]; do
 done
 
 ori_dir=${PWD}
-cd /src/sat_pubsub/db
+cd /src/libervia-pubsub/db
 
 # PG should be OK, we now initialize the database. If it's already done, it will fail
 # with exit code 3