Help text defaults unnecessary / inaccurate

[brandond]

The command-line argument defaults are duplicated in the help text, and are (at times) inaccurate.

Usage of /metrics-sidecar:
  -db-file string
        What file to use as a SQLite3 database. Defaults to ':memory:' (default ":memory:")
  -kubeconfig string
        absolute path to the kubeconfig file
  -max-window int
        Window of time you wish to retain records (in minutes). Defaults to '15' (default 15)
  -refresh-interval int
        Frequency (in seconds) to update the metrics database. Defaults to '5' (default 10)