NullReferenceException in ApplicationInsightsLogger.Log when exception contains a Data entry with a null value #1436

If you are reporting bug/issue, please provide detailed Repro instructions.

Repro Steps

var exception = new System.Exception();
exception.Data["foo"] = null;
throw exception;

Actual Behavior

Response exception in middleware: System.AggregateException: An error occurred while writing to logger(s). (Object reference not set to an instance of an object.) ---> System.NullReferenceException: Object reference not set to an instance of an object. at Microsoft.ApplicationInsights.AspNetCore.Logging.ApplicationInsightsLogger.<>c__DisplayClass9_01.<Log>b__0(DictionaryEntry item) at System.Collections.Generic.List1.ForEach(Action1 action) at Microsoft.ApplicationInsights.AspNetCore.Logging.ApplicationInsightsLogger.Log[TState](LogLevel logLevel, EventId eventId, TState state, Exception exception, Func3 formatter) at Microsoft.Extensions.Logging.Logger.Log[TState](LogLevel logLevel, EventId eventId, TState state, Exception exception, Func3 formatter) --- End of inner exception stack trace --- at Microsoft.Extensions.Logging.Logger.Log[TState](LogLevel logLevel, EventId eventId, TState state, Exception exception, Func3 formatter) at Microsoft.Extensions.Logging.LoggerExtensions.Log(ILogger logger, LogLevel logLevel, EventId eventId, Exception exception, String message, Object[] args) at Microsoft.Extensions.Logging.LoggerExtensions.LogError(ILogger logger, EventId eventId, Exception exception, String message, Object[] args)

Expected Behavior

Logs an exception

Version Info

SDK Version : 2.5.1
.NET Version : .NET core 2.2
How Application was onboarded with SDK(VisualStudio/StatusMonitor/Azure Extension) :
OS : Windows
Hosting Info (IIS/Azure WebApps/ etc) :