Fix flake in RabbitMQ DSM snapshots across bucket boundaries (#8972)

## Summary of changes

Since the DSM stats are aggregated in 10 second buckes the same pathway
can appear more than once, so this goes and groups them and then grabs
the first only.

## Reason for change

Flaked here
https://dev.azure.com/datadoghq/a51c4863-3eb4-4c5d-878a-58b41a049e4e/_build/results?buildId=206016&view=logs&j=0cad3504-1a92-5a43-34ae-f4023f981687&t=0b455496-9860-5768-a99e-6f5c6c3cdcbd

and the cause was that the snapshots changed.

## Implementation details

## Test coverage

Same

## Other details
<!-- Fixes #{issue} -->

#incident-57303
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Author: bouwkast

tracer/test/Datadog.Trace.ClrProfiler.IntegrationTests/DataStreamsMonitoringRabbitMQTests.cs

@@ -89,6 +89,12 @@ private static IList<MockDataStreamsStatsPoint> PayloadsToPoints(IImmutableList<
             }
         }
 
-        return points.OrderBy(s => s.Hash).ThenBy(s => s.TimestampType).ToList();
+        // Stats points are aggregated by hash within 10-second buckets. If the sample crosses a
+        // bucket boundary, the same pathway can appear more than once in the collected payloads.
+        return points.GroupBy(s => new { s.Hash, s.ParentHash, s.TimestampType })
+                     .Select(g => g.First())
+                     .OrderBy(s => s.Hash)
+                     .ThenBy(s => s.TimestampType)
+                     .ToList();
     }
 }