unsubscribe: Change render_to_response to render.
unsubscribe: Change render_to_response to render.

Related to #4093

j831/zulip,brockwhittaker/zulip,j831/zulip,dawran6/zulip,jphilipsen05/zulip,dawran6/zulip,shubhamdhama/zulip,zulip/zulip,shubhamdhama/zulip,jackrzhang/zulip,kou/zulip,dhcrzf/zulip,j831/zulip,SmartPeople/zulip,tommyip/zulip,susansls/zulip,dawran6/zulip,andersk/zulip,timabbott/zulip,dawran6/zulip,vabs22/zulip,showell/zulip,ryanbackman/zulip,rht/zulip,vabs22/zulip,jainayush975/zulip,mahim97/zulip,punchagan/zulip,synicalsyntax/zulip,rht/zulip,brainwane/zulip,jainayush975/zulip,jphilipsen05/zulip,aakash-cr7/zulip,timabbott/zulip,susansls/zulip,brainwane/zulip,eeshangarg/zulip,jphilipsen05/zulip,vaidap/zulip,zulip/zulip,punchagan/zulip,synicalsyntax/zulip,eeshangarg/zulip,zulip/zulip,verma-varsha/zulip,brainwane/zulip,susansls/zulip,eeshangarg/zulip,timabbott/zulip,Galexrt/zulip,kou/zulip,synicalsyntax/zulip,jrowan/zulip,verma-varsha/zulip,SmartPeople/zulip,aakash-cr7/zulip,jackrzhang/zulip,christi3k/zulip,hackerkid/zulip,rht/zulip,j831/zulip,punchagan/zulip,jphilipsen05/zulip,vabs22/zulip,brainwane/zulip,vaidap/zulip,JPJPJPOPOP/zulip,JPJPJPOPOP/zulip,brockwhittaker/zulip,hackerkid/zulip,vabs22/zulip,zulip/zulip,Galexrt/zulip,Galexrt/zulip,showell/zulip,SmartPeople/zulip,showell/zulip,dawran6/zulip,rht/zulip,amanharitsh123/zulip,showell/zulip,shubhamdhama/zulip,susansls/zulip,vaidap/zulip,vaidap/zulip,showell/zulip,hackerkid/zulip,jrowan/zulip,verma-varsha/zulip,Galexrt/zulip,dhcrzf/zulip,ryanbackman/zulip,rishig/zulip,christi3k/zulip,Galexrt/zulip,shubhamdhama/zulip,j831/zulip,jphilipsen05/zulip,jackrzhang/zulip,jackrzhang/zulip,dhcrzf/zulip,brockwhittaker/zulip,brockwhittaker/zulip,brainwane/zulip,kou/zulip,zulip/zulip,andersk/zulip,rishig/zulip,vaidap/zulip,dhcrzf/zulip,eeshangarg/zulip,christi3k/zulip,jackrzhang/zulip,aakash-cr7/zulip,shubhamdhama/zulip,verma-varsha/zulip,brainwane/zulip,brainwane/zulip,JPJPJPOPOP/zulip,kou/zulip,andersk/zulip,tommyip/zulip,punchagan/zulip,susansls/zulip,christi3k/zulip,rht/zulip,amanharitsh123/zulip,amanharitsh123/zulip,showell/zulip,vabs22/zulip,timabbott/zulip,jackrzhang/zulip,amanharitsh123/zulip,jrowan/zulip,showell/zulip,punchagan/zulip,ryanbackman/zulip,JPJPJPOPOP/zulip,jphilipsen05/zulip,SmartPeople/zulip,timabbott/zulip,SmartPeople/zulip,rishig/zulip,rishig/zulip,hackerkid/zulip,rht/zulip,verma-varsha/zulip,tommyip/zulip,ryanbackman/zulip,rishig/zulip,jackrzhang/zulip,jainayush975/zulip,synicalsyntax/zulip,aakash-cr7/zulip,jrowan/zulip,tommyip/zulip,hackerkid/zulip,rht/zulip,hackerkid/zulip,zulip/zulip,dawran6/zulip,JPJPJPOPOP/zulip,shubhamdhama/zulip,JPJPJPOPOP/zulip,christi3k/zulip,verma-varsha/zulip,aakash-cr7/zulip,mahim97/zulip,vaidap/zulip,shubhamdhama/zulip,vabs22/zulip,eeshangarg/zulip,susansls/zulip,amanharitsh123/zulip,ryanbackman/zulip,timabbott/zulip,zulip/zulip,mahim97/zulip,kou/zulip,rishig/zulip,kou/zulip,kou/zulip,jainayush975/zulip,christi3k/zulip,mahim97/zulip,tommyip/zulip,andersk/zulip,mahim97/zulip,synicalsyntax/zulip,synicalsyntax/zulip,synicalsyntax/zulip,punchagan/zulip,tommyip/zulip,jrowan/zulip,andersk/zulip,timabbott/zulip,Galexrt/zulip,punchagan/zulip,andersk/zulip,dhcrzf/zulip,aakash-cr7/zulip,j831/zulip,jrowan/zulip,mahim97/zulip,eeshangarg/zulip,brockwhittaker/zulip,brockwhittaker/zulip,jainayush975/zulip,Galexrt/zulip,ryanbackman/zulip,rishig/zulip,dhcrzf/zulip,dhcrzf/zulip,amanharitsh123/zulip,hackerkid/zulip,jainayush975/zulip,tommyip/zulip,eeshangarg/zulip,andersk/zulip,SmartPeople/zulip