Add missing argument

Author: apasel422

api.bs

@@ -2258,7 +2258,8 @@ and [=response=] |response|, run these steps:
 
         1.  Let |reportPromise| be the result of running [=measure a conversion=] with |conversionOptions| and |implicitInputs|.
 
-        1.  [=In parallel=], [=upon fulfillment=] of |reportPromise|, [=send a report=] with its value and |reportUrl|.
+        1.  [=In parallel=], [=upon fulfillment=] of |reportPromise|, [=send a report=] with the fulfilled value, |reportUrl|, and
+            |request|'s [=request/client=].
 
 Issue: Confirm the desired semantics of [:Save-Impression:] and [:Measure-Conversion:] in the same response.