OverflowException in MetricsEventManager.RaiseMetricsPerFunctionEvent

[jviau]

Kusto logs are showing an overflow exception here for some customer apps:

System.OverflowException : Value was either too large or too small for a UInt64.
    at System.Decimal.ToUInt64(Decimal d)
    at System.Convert.ToUInt64(Decimal value)
    at Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics.MetricsEventManager.FunctionActivityTracker.<>c.<RaiseMetricsPerFunctionEvent>b__29_1(IGrouping`2 functionGroups)
    at /_/src/WebJobs.Script.WebHost/Diagnostics/MetricsEventManager.cs : 556
    at System.Linq.Enumerable.SelectEnumerableIterator`2.MoveNext()
    at Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics.MetricsEventManager.FunctionActivityTracker.RaiseMetricsPerFunctionEvent()
    at /_/src/WebJobs.Script.WebHost/Diagnostics/MetricsEventManager.cs : 565
    at Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics.MetricsEventManager.FunctionActivityTracker.TimerFlush(Object state)
    at /_/src/WebJobs.Script.WebHost/Diagnostics/MetricsEventManager.cs : 382