Fix grouped aggregation memory tracking

Author: pettyjamesm

core/trino-main/src/main/java/io/trino/operator/aggregation/builder/InMemoryHashAggregationBuilder.java

@@ -228,15 +228,17 @@ public long getGroupCount()
     @Override
     public WorkProcessor<Page> buildResult()
     {
+        groupByHash.startReleasingOutput();
         for (GroupedAggregator groupedAggregator : groupedAggregators) {
             groupedAggregator.prepareFinal();
         }
-        // Only incrementally release memory for final aggregations, since partial aggregations have a fixed
-        // memory limit and can be expected to fully flush and release their output quickly
+        // Always update the current memory usage after calling GroupedAggregator#prepareFinal(), since it can increase
+        // memory consumption significantly in some situations. This also captures any memory usage reduction the
+        // groupByHash may have initiated for releasing output
+        updateMemory();
+        // Only incrementally release memory while producing output for final aggregations, since partial aggregations
+        // have a fixed memory limit and can be expected to fully flush and release their output quickly
         boolean releaseMemoryOnOutput = !partial;
-        if (releaseMemoryOnOutput) {
-            groupByHash.startReleasingOutput();
-        }
         return buildResult(consecutiveGroupIds(), new PageBuilder(buildTypes()), false, releaseMemoryOnOutput);
     }