queue: Remove a no-longer-correct comment.
queue: Remove a no-longer-correct comment.

This comment stopped being true in 5686821150, and very much stopped
being relevant in dd40649e04 when the middleware entirely stopped
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zulip/zulip,andersk/zulip,brainwane/zulip,zulip/zulip,hackerkid/zulip,rht/zulip,rht/zulip,showell/zulip,kou/zulip,kou/zulip,hackerkid/zulip,kou/zulip,andersk/zulip,showell/zulip,hackerkid/zulip,punchagan/zulip,showell/zulip,brainwane/zulip,punchagan/zulip,kou/zulip,brainwane/zulip,eeshangarg/zulip,zulip/zulip,kou/zulip,hackerkid/zulip,andersk/zulip,eeshangarg/zulip,eeshangarg/zulip,hackerkid/zulip,rht/zulip,brainwane/zulip,rht/zulip,punchagan/zulip,punchagan/zulip,eeshangarg/zulip,zulip/zulip,andersk/zulip,brainwane/zulip,andersk/zulip,zulip/zulip,andersk/zulip,eeshangarg/zulip,eeshangarg/zulip,rht/zulip,punchagan/zulip,zulip/zulip,eeshangarg/zulip,hackerkid/zulip,brainwane/zulip,punchagan/zulip,showell/zulip,kou/zulip,brainwane/zulip,rht/zulip,kou/zulip,andersk/zulip,showell/zulip,hackerkid/zulip,rht/zulip,showell/zulip,showell/zulip,zulip/zulip,punchagan/zulip