openapi: Edit `/events` OpenAPI specification for validation.
openapi: Edit `/events` OpenAPI specification for validation.

Some events in `/events` were incorrectly or incompletely documented.
Rectify them.

hackerkid/zulip,punchagan/zulip,punchagan/zulip,showell/zulip,hackerkid/zulip,hackerkid/zulip,rht/zulip,punchagan/zulip,kou/zulip,rht/zulip,showell/zulip,brainwane/zulip,kou/zulip,brainwane/zulip,brainwane/zulip,zulip/zulip,hackerkid/zulip,rht/zulip,eeshangarg/zulip,showell/zulip,zulip/zulip,andersk/zulip,eeshangarg/zulip,kou/zulip,andersk/zulip,brainwane/zulip,showell/zulip,punchagan/zulip,andersk/zulip,rht/zulip,andersk/zulip,kou/zulip,rht/zulip,showell/zulip,hackerkid/zulip,andersk/zulip,eeshangarg/zulip,brainwane/zulip,punchagan/zulip,kou/zulip,rht/zulip,showell/zulip,zulip/zulip,brainwane/zulip,zulip/zulip,eeshangarg/zulip,kou/zulip,kou/zulip,eeshangarg/zulip,eeshangarg/zulip,punchagan/zulip,showell/zulip,andersk/zulip,hackerkid/zulip,zulip/zulip,punchagan/zulip,eeshangarg/zulip,zulip/zulip,brainwane/zulip,andersk/zulip,rht/zulip,zulip/zulip,hackerkid/zulip