EC2 AutoDetect detector does not apply custom filters passed via filter_ parameter

[l-kirschner]

Hey guys!
Thank you for the amazing library. While working with the EC2 CPU AutoDetect detector, I noticed that filters don't seem to be applied correctly.

For example, this line doesn't appear to honor the specified filter:

ec2.cpu_utilization_detector(filter_=filter('aws_tag_Name', 'myserver-*')).publish('Logging Infrastructure (EC2): CPU utilization expected to reach the limit')

After some digging, I traced the issue to this line in the source:
https://github.com/signalfx/signalflow-library/blob/master/library/signalfx/detectors/autodetect/infra/aws/ec2.flow#L121

It looks like the filter_ parameter isn’t being passed along to the data stream.