Scheduled weekly dependency update for week 18 (#279)
Scheduled weekly dependency update for week 18 (#279)

* Update attrs from 17.4.0 to 18.1.0

* Update pytest-mock from 1.9.0 to 1.10.0

* Update aiohttp from 3.1.3 to 3.2.0

* Update multidict from 4.1.0 to 4.3.0

* Update yarl from 1.1.1 to 1.2.3

aio-libs/aiohttp_session