remove redundant/accidental line in query doc
@@ -179,8 +179,6 @@ for each of the given times in UTC. Returned values are from 0 to 23.
## `idelta()`
-`idelta(v range-vector)`
-
`idelta(v range-vector)` calculates the difference between the last two samples
in the range vector `v`, returning an instant vector with the given deltas and
equivalent labels.
