Remove the aws_ec2 crash method in powertest.py and all EC2-control logic used by the crash method including the following:

• is_instance_running(). We assume the instance is always running.
• all instances of aws_ec2 in code and in strings in powertest.py
• imports and all usages of the {{aws_ec2]} module
• buildscripts/aws_ec2.py (yes the entire file)
• buildscripts/launch_evergreen_ec2_instance.sh
• Parts of the SetUpEC2Instance class in plugins.py based on the POC, The file may have moved by the time this ticket is worked on.