[server] prevent returning closed cursor to the database pool In since c8c6ad8 init_repository use repo.internal_cnx() instead of repo.system_source.get_connection() so it use the pool and we should not close cursors from the pool before returning it back. Otherwise we may have "connection already closed" error. This bug only trigger when connection-pool-size = 1. Since we are moving to use a dynamic pooler we need to get this fixed. This does not occur with sqlite since the connection wrapper instantiate new cursor everytime, but this occur with other databases.

### Requirements for tests in various cubicweb/**/test directories. ###

## shared by several test folders
docutils
webtest

## cubicweb/test
Pygments
pycryptodomex
#fyzz XXX pip install fails

## cubicweb/devtools/test
flake8

## cubicweb/hooks/test
psycopg2-binary

## cubicweb/pyramid/test
pyramid >= 1.5.0
waitress >= 0.8.9
wsgicors >= 0.3
pyramid_multiauth
repoze.lru

## cubicweb/sobject/test