Fix location of returns

Author: ocelotl

opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/aggregation.py

@@ -278,17 +278,14 @@ def collect(
                     is AggregationTemporality.DELTA
                 ):
 
-                    if value is None:
-                        return None
-
                     previous_collection_start_nano = (
                         self._previous_collection_start_nano
                     )
                     self._previous_collection_start_nano = (
                         collection_start_nano
                     )
 
-                    if current_value is None:
+                    if value is None:
                         return None
 
                     return NumberDataPoint(
@@ -473,17 +470,14 @@ def collect(
                     is AggregationTemporality.DELTA
                 ):
 
-                    if value is None:
-                        return None
-
                     previous_collection_start_nano = (
                         self._previous_collection_start_nano
                     )
                     self._previous_collection_start_nano = (
                         collection_start_nano
                     )
 
-                    if current_value is None:
+                    if value is None:
                         return None
 
                     return HistogramDataPoint(