AplicationInsightsLoggerProvider does not catch exceptions.

[cijothomas]

Describe the bug

AplicationInsightsLoggerProvider is not catching exceptions and letting them propagate to caller. This can cause applications to crash if an exception occurs inside ApplicationInsightsProvider. This is against the overall SDK principles of never throwing.
https://github.com/microsoft/ApplicationInsights-dotnet/blob/develop/LOGGING/src/ILogger/ApplicationInsightsLogger.cs#L79

Proposal : catch and log exception to EventSource.

[cijothomas]

This was found another part of AI SDK did not handle exception:
https://github.com/microsoft/ApplicationInsights-dotnet/blob/develop/BASE/src/Microsoft.ApplicationInsights/DataContracts/ExceptionTelemetry.cs#L208

Its also important to fix the underlying ExceptionTelemetry class to never throw.

Example exception trace:

2020-07-15T11:33:59.315067545Z System.AggregateException: An error occurred while writing to logger(s). (Invalid assembly public key. (0x8013141E))
2020-07-15T11:33:59.321326827Z  ---> System.Security.SecurityException: Invalid assembly public key. (0x8013141E)
2020-07-15T11:33:59.321343928Z    at System.Reflection.RuntimeAssembly.GetFullName(QCallAssembly assembly, StringHandleOnStack retString)
2020-07-15T11:33:59.321350228Z    at System.Reflection.RuntimeAssembly.get_FullName()
2020-07-15T11:33:59.321684343Z    at Microsoft.ApplicationInsights.Extensibility.Implementation.ExceptionConverter.GetStackFrame(StackFrame stackFrame, Int32 frameId)
2020-07-15T11:33:59.321697944Z    at Microsoft.ApplicationInsights.Extensibility.Implementation.ExceptionConverter.SanitizeStackFrame[TInput,TOutput](IList`1 inputList, Func`3 converter, Func`2 lengthGetter)
2020-07-15T11:33:59.321704144Z    at Microsoft.ApplicationInsights.Extensibility.Implementation.ExceptionConverter.ConvertToExceptionDetails(Exception exception, ExceptionDetails parentExceptionDetails)
2020-07-15T11:33:59.321717044Z    at Microsoft.ApplicationInsights.DataContracts.ExceptionTelemetry.ConvertExceptionTree(Exception exception, ExceptionDetails parentExceptionDetails, List`1 exceptions)
2020-07-15T11:33:59.321721845Z    at Microsoft.ApplicationInsights.DataContracts.ExceptionTelemetry.UpdateData(Exception exception)
2020-07-15T11:33:59.321726545Z    at Microsoft.ApplicationInsights.DataContracts.ExceptionTelemetry.set_Exception(Exception value)
2020-07-15T11:33:59.321731245Z    at Microsoft.ApplicationInsights.DataContracts.ExceptionTelemetry..ctor(Exception exception)
2020-07-15T11:33:59.322066560Z    at Microsoft.Extensions.Logging.ApplicationInsights.ApplicationInsightsLogger.Log[TState](LogLevel logLevel, EventId eventId, TState state, Exception exception, Func`3 formatter)