Job Monitor errors and failed work item info should make it into the timeline

[mmitche]

When a work item fails, the job monitor should print this information to the console in a way that esnures it makes it into the AzDO build timeline.

This should happen for warnings and errors, and involves adding a prefix to the logging. Consider doing the following:

• Introduce a helper method to log errors and warnings, rather than talking directly to the logger API.
• Helper method prefixes the appropriate azdo log message.

Additional things to look for:

• Console.WRiteLine should NOT be in use in the job monitor. Only use the logger.