tornado: Fix missing mypy annotation.
tornado: Fix missing mypy annotation.

rishig/zulip,hackerkid/zulip,jackrzhang/zulip,synicalsyntax/zulip,kou/zulip,rishig/zulip,eeshangarg/zulip,punchagan/zulip,synicalsyntax/zulip,showell/zulip,zulip/zulip,zulip/zulip,dhcrzf/zulip,shubhamdhama/zulip,jackrzhang/zulip,showell/zulip,rht/zulip,rishig/zulip,jackrzhang/zulip,eeshangarg/zulip,synicalsyntax/zulip,synicalsyntax/zulip,hackerkid/zulip,dhcrzf/zulip,brainwane/zulip,timabbott/zulip,hackerkid/zulip,shubhamdhama/zulip,timabbott/zulip,rht/zulip,andersk/zulip,eeshangarg/zulip,shubhamdhama/zulip,rht/zulip,zulip/zulip,shubhamdhama/zulip,showell/zulip,timabbott/zulip,timabbott/zulip,andersk/zulip,rht/zulip,brainwane/zulip,brainwane/zulip,kou/zulip,tommyip/zulip,shubhamdhama/zulip,shubhamdhama/zulip,hackerkid/zulip,rishig/zulip,tommyip/zulip,kou/zulip,andersk/zulip,andersk/zulip,zulip/zulip,rishig/zulip,showell/zulip,zulip/zulip,jackrzhang/zulip,synicalsyntax/zulip,dhcrzf/zulip,showell/zulip,zulip/zulip,jackrzhang/zulip,tommyip/zulip,punchagan/zulip,brainwane/zulip,eeshangarg/zulip,dhcrzf/zulip,dhcrzf/zulip,punchagan/zulip,dhcrzf/zulip,jackrzhang/zulip,brainwane/zulip,tommyip/zulip,eeshangarg/zulip,punchagan/zulip,tommyip/zulip,hackerkid/zulip,kou/zulip,brainwane/zulip,kou/zulip,rishig/zulip,timabbott/zulip,hackerkid/zulip,dhcrzf/zulip,timabbott/zulip,zulip/zulip,tommyip/zulip,showell/zulip,andersk/zulip,synicalsyntax/zulip,tommyip/zulip,rht/zulip,shubhamdhama/zulip,punchagan/zulip,eeshangarg/zulip,punchagan/zulip,brainwane/zulip,andersk/zulip,kou/zulip,andersk/zulip,timabbott/zulip,showell/zulip,rht/zulip,eeshangarg/zulip,rht/zulip,punchagan/zulip,kou/zulip,jackrzhang/zulip,hackerkid/zulip,synicalsyntax/zulip,rishig/zulip