update tox.ini to cover 292 succeeding tests
update tox.ini to cover 292 succeeding tests

Signed-Off-By: Matthias Kesler <dd3fe5b310b90e6417c53f71f6ae7b2833a6a90b@krombel.de>

matrix-org/synapse,matrix-org/synapse,matrix-org/synapse,matrix-org/synapse,matrix-org/synapse,matrix-org/synapse