AggregatorStore: don't double-count drops in doubles

As funny as double counting only in doubles is, this seems like an oversight where we inadvertently call `Interlocked.Increment(ref this.DroppedMeasurements);` twice in the non-`emitOverflowAttribute` path. I noticed this digging into a related issue, so thought I'd pop up a PR while in here :)

src/OpenTelemetry/Metrics/AggregatorStore.cs

@@ -1033,7 +1033,6 @@ private void UpdateDouble(double value, ReadOnlySpan<KeyValuePair<string, object
                         OpenTelemetrySdkEventSource.Log.MeasurementDropped(this.name, this.metricPointCapHitMessage, MetricPointCapHitFixMessage);
                     }
 
-                    Interlocked.Increment(ref this.DroppedMeasurements);
                     return;
                 }
             }
@@ -1078,7 +1077,6 @@ private void UpdateDoubleCustomTags(double value, ReadOnlySpan<KeyValuePair<stri
                         OpenTelemetrySdkEventSource.Log.MeasurementDropped(this.name, this.metricPointCapHitMessage, MetricPointCapHitFixMessage);
                     }
 
-                    Interlocked.Increment(ref this.DroppedMeasurements);
                     return;
                 }
             }