Atlas's ETA is too optimistic

- app version: Cardinal Maps 0.16.1-arm64

The problem

Describe precisely the problem you're facing and add screenshots to illustrate

When I was arriving near my destination I realized the ETA had changed and Atlas was estimating I would walk 400 meters in less than a minute (it changed to 300m when I was taking the screenshot)

Additional irrealistic ETAs

Steps to reproduce

Technical details

Paste any relevant logs (adb logcat) in the codeblock below if you have any

/cc @ellenhp