Add Sentry Logging for missing Course/Instructor values

[ChaseC99]

We should add logging to notify us when a course id or instructor is missing from our datasets.
The log would get triggered when a grades or schedule query tries to access the cache and finds that one is missing.

[ramanxg]

In the course_offerring type, we search our cache to find the matching information on a professor, or course, it is not always in our cache. In this case, we need to log this in Sentry. Sentry is already setup, in the project, all that has to occur is when this event occurs, we should send an event to Sentry.

This is an example of one of an instructor that is currently not in our cache:

{
  grades(instructor:"SHEPHERD, B.") {
    grade_distributions {
      course_offering {
        instructors {
          name
          ucinetid
          shortened_name
        }
      }
    }
  }
}

An example of a course not in our cache:

{
  grades(department:"CSE", number:"31") {
    grade_distributions {
      course_offering {
        course {
          description
          id
        }
      }
    }
  }
}