decorator: Remove redundant tests for api_key_only_webhook_view.
decorator: Remove redundant tests for api_key_only_webhook_view.

We do not need to test the exception message being logged in every
test case where an exception is raised by a webhook function.
Testing it once should be enough; this makes the tests less
verbose.

rht/zulip,timabbott/zulip,dhcrzf/zulip,tommyip/zulip,rht/zulip,tommyip/zulip,showell/zulip,vaidap/zulip,showell/zulip,synicalsyntax/zulip,synicalsyntax/zulip,rht/zulip,shubhamdhama/zulip,jackrzhang/zulip,dhcrzf/zulip,eeshangarg/zulip,andersk/zulip,shubhamdhama/zulip,brainwane/zulip,rishig/zulip,punchagan/zulip,jackrzhang/zulip,zulip/zulip,rht/zulip,mahim97/zulip,verma-varsha/zulip,amanharitsh123/zulip,timabbott/zulip,Galexrt/zulip,tommyip/zulip,showell/zulip,hackerkid/zulip,Galexrt/zulip,andersk/zulip,shubhamdhama/zulip,timabbott/zulip,showell/zulip,brockwhittaker/zulip,brockwhittaker/zulip,punchagan/zulip,brockwhittaker/zulip,Galexrt/zulip,zulip/zulip,andersk/zulip,punchagan/zulip,punchagan/zulip,punchagan/zulip,verma-varsha/zulip,tommyip/zulip,kou/zulip,timabbott/zulip,Galexrt/zulip,zulip/zulip,Galexrt/zulip,brockwhittaker/zulip,synicalsyntax/zulip,timabbott/zulip,andersk/zulip,synicalsyntax/zulip,vabs22/zulip,hackerkid/zulip,dhcrzf/zulip,zulip/zulip,eeshangarg/zulip,jackrzhang/zulip,Galexrt/zulip,punchagan/zulip,eeshangarg/zulip,mahim97/zulip,kou/zulip,andersk/zulip,zulip/zulip,brainwane/zulip,kou/zulip,brainwane/zulip,brockwhittaker/zulip,showell/zulip,hackerkid/zulip,eeshangarg/zulip,andersk/zulip,synicalsyntax/zulip,zulip/zulip,jackrzhang/zulip,jackrzhang/zulip,tommyip/zulip,rht/zulip,vabs22/zulip,vabs22/zulip,vaidap/zulip,synicalsyntax/zulip,kou/zulip,showell/zulip,shubhamdhama/zulip,rishig/zulip,andersk/zulip,vaidap/zulip,kou/zulip,tommyip/zulip,timabbott/zulip,verma-varsha/zulip,mahim97/zulip,shubhamdhama/zulip,eeshangarg/zulip,showell/zulip,vabs22/zulip,synicalsyntax/zulip,dhcrzf/zulip,amanharitsh123/zulip,vaidap/zulip,mahim97/zulip,verma-varsha/zulip,dhcrzf/zulip,amanharitsh123/zulip,vaidap/zulip,rishig/zulip,vabs22/zulip,rishig/zulip,hackerkid/zulip,kou/zulip,hackerkid/zulip,vabs22/zulip,dhcrzf/zulip,vaidap/zulip,hackerkid/zulip,brainwane/zulip,amanharitsh123/zulip,rht/zulip,rishig/zulip,jackrzhang/zulip,eeshangarg/zulip,Galexrt/zulip,zulip/zulip,rishig/zulip,amanharitsh123/zulip,tommyip/zulip,hackerkid/zulip,shubhamdhama/zulip,brockwhittaker/zulip,timabbott/zulip,kou/zulip,brainwane/zulip,brainwane/zulip,verma-varsha/zulip,shubhamdhama/zulip,punchagan/zulip,dhcrzf/zulip,mahim97/zulip,jackrzhang/zulip,rht/zulip,rishig/zulip,eeshangarg/zulip,amanharitsh123/zulip,mahim97/zulip,brainwane/zulip,verma-varsha/zulip