[BUG] Custom properties added with addTelemetryInitializer are ignored for exceptions

[Trenrod]

Description/Screenshot
Custom properties added with addTelemetryInitializer are ignored for exceptions

Custom property session_id is only send for custom events. It is not send with any exception

Steps to Reproduce
init telemetry with custom properties

        const telemetryInitializer = (item: ITelemetryItem) => {
            if (item.data !== undefined) {
                item.data.session_id = theConferenceController.getClientSessionIdentifier();
            }
        };
        appInsights.loadAppInsights();
        appInsights.addTelemetryInitializer(telemetryInitializer);

Calling examples

      getAppInsights()?.trackEvent({name: "TEST"});
      throw Error("This is just a test, calm down");
    } catch (error) {
      getAppInsights()?.trackException(error);

• OS/Browser:
  Chrome: Version 81.0.4044.129 (Offizieller Build) (64-Bit)
• SDK Version [e.g. 22]:
  "@microsoft/applicationinsights-react-js": "^2.5.4",
  "@microsoft/applicationinsights-web": "^2.5.4",
• How you initialized the SDK:
  https://github.com/Azure-Samples/application-insights-react-demo/blob/master/src/TelemetryService.js

Expected behavior
session_id should also be send on exception like it is send when custom events are triggered.

Additional context
No

[MSNev]

This is an issue with the way that the exception envelope is created.
I have a work item around enhancing the way the exceptions are serialized (part of a fix for #363), I'll see if I can address this at the same time.

[MSNev]

I'm also tagging as an enhancement as it appears to have been like this for a while -- it assumes that custom properties are passed to the trackException() which they aren't for automatically caught exceptions

[riteshbhoi]

i had raised this issue almost a year back and it was closed stating this was fixed.
reference: #954

[MSNev]

Release is now fully deployed

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.