test: Add tests for findDistanceTraveled function

[ericahagle]

Description

• Update findDistanceTraveled function to return total distance traveled for a user on a given day
• Add tests for findDistanceTraveled function

Contributors

@ericahagle

Notes

• The function originally returned distance based on the dailyStepGoal, but needed to return distance based on numSteps, so that update is included in this PR.

Checklist

• [x] My PR has an appropriately descriptive and concise title.
• [x] My PR denotes any/all team members who contributed to it.
• [x] My code follows the Turing Style Guides and best practices.
• [x] I ran the code locally and verified that there are no visible errors.
• [x] test: My PR clearly describes the test(s) I'm adding, and specifies for which function. (if applicable)
• [x] fix: My PR clearly describes what bug I'm fixing and why. (if applicable)

[ericahagle]

I tried to figure out how to test a negative scenario (no available activity data) but kept running into undefined issues, making me think that the function would have to be altered further in order to handle this gracefully. If anyone has ideas, I'd love to get that working. If not, I think just the happy path is good enough for now considering the api data itself.

[tenthwalker]

I'm good with just testing the happy path for now and flagging this as an opportunity for refactoring later.