Describe the bug
When running activities.ipynb, I noticed that the Pace value is displaying a per mile pace, but the rest of the DB is metric, See attached imaged.

To Reproduce
Steps to reproduce the behavior:
- Garmin Connect units set to kmph
- Create database using garmindb_cli.py
- Run activities.ipynb
- See error
Expected behavior
The pace calculations should be per kilometer.
Additional context
I have traced this and would like to suggest a change to ActivityFitFileProcessor._write_steps_entry().
My current guess is that GarminConnect stores the pace information as mph which converts nicely to the numbers shown in the attached image. I tried working on a solution for this, but am not sure where to get the measurement system information in this processor file to write an if ... else .. statement to handle this.