confirmation: Fix mypy annotation in create_confirmation_link.
confirmation: Fix mypy annotation in create_confirmation_link.

zulip/zulip,synicalsyntax/zulip,shubhamdhama/zulip,timabbott/zulip,synicalsyntax/zulip,rishig/zulip,rht/zulip,zulip/zulip,timabbott/zulip,eeshangarg/zulip,dhcrzf/zulip,punchagan/zulip,eeshangarg/zulip,punchagan/zulip,mahim97/zulip,dhcrzf/zulip,eeshangarg/zulip,dhcrzf/zulip,dhcrzf/zulip,hackerkid/zulip,mahim97/zulip,zulip/zulip,zulip/zulip,brainwane/zulip,timabbott/zulip,brainwane/zulip,andersk/zulip,synicalsyntax/zulip,andersk/zulip,rht/zulip,shubhamdhama/zulip,kou/zulip,rishig/zulip,brainwane/zulip,kou/zulip,tommyip/zulip,brainwane/zulip,hackerkid/zulip,eeshangarg/zulip,shubhamdhama/zulip,dhcrzf/zulip,punchagan/zulip,jackrzhang/zulip,eeshangarg/zulip,tommyip/zulip,hackerkid/zulip,shubhamdhama/zulip,hackerkid/zulip,rishig/zulip,synicalsyntax/zulip,timabbott/zulip,eeshangarg/zulip,zulip/zulip,mahim97/zulip,brainwane/zulip,hackerkid/zulip,shubhamdhama/zulip,rht/zulip,showell/zulip,kou/zulip,kou/zulip,kou/zulip,andersk/zulip,andersk/zulip,jackrzhang/zulip,rht/zulip,andersk/zulip,rishig/zulip,punchagan/zulip,rishig/zulip,synicalsyntax/zulip,mahim97/zulip,hackerkid/zulip,punchagan/zulip,tommyip/zulip,brainwane/zulip,punchagan/zulip,hackerkid/zulip,rht/zulip,jackrzhang/zulip,rishig/zulip,dhcrzf/zulip,jackrzhang/zulip,jackrzhang/zulip,timabbott/zulip,zulip/zulip,tommyip/zulip,rht/zulip,synicalsyntax/zulip,tommyip/zulip,showell/zulip,synicalsyntax/zulip,showell/zulip,zulip/zulip,kou/zulip,eeshangarg/zulip,tommyip/zulip,jackrzhang/zulip,timabbott/zulip,showell/zulip,kou/zulip,jackrzhang/zulip,showell/zulip,showell/zulip,andersk/zulip,tommyip/zulip,andersk/zulip,mahim97/zulip,shubhamdhama/zulip,timabbott/zulip,dhcrzf/zulip,showell/zulip,punchagan/zulip,mahim97/zulip,rht/zulip,brainwane/zulip,shubhamdhama/zulip,rishig/zulip