Enable Sentry error monitoring

[heykarimoff]

Enable sending errors/exceptions to Sentry monitoring system. This PR completes a part of #17 which does the following:

• Install sentry-sdk@2.15.0
• Configure sentry in django settings with default values.

[a-musing-moose]

Thanks for this - I don't think that we should include a view for triggering errors that anyone can visit at any time.

[G-Rath]

I've added details about what our traditional settings are for Sentry across our apps - otherwise this looks good.

I would also suggest possibly adding this as a commented out line after the config:

sentry_sdk.integrations.logging.ignore_logger("django.security.DisallowedHost")

because

1. sometimes our apps have reasons for requests that trigger this error in which case we don't want to be told about it
   • i.e. one client runs tennable.io from behind their WAF, and another client manages the infrastructure and has decided to make the app publicly accessible - in both cases, this error is the correct and desired response, so it just creates noise having it reported to Sentry
2. it strongly hints at how you can handle these kind of errors in situations where they're overly noisy, as it doesn't seem to be signposted well enough
   • for some reason the most common solution I see people PRing is creating a custom before_send filter, which as things go isn't the worst thing, but it's still more complex than this 😅

The issue has been resolved.