Getting workout routes for workout UUID

[karolinaoparczyk]

Is your feature request related to a problem? Please describe.
Getting workout routes with time interval Predicate starting and ending at the time of the workout doesn't explicitly return routes of this workout. We get some (or no) routes without any information in them to which workout they belong to.
I haven't got any results when trying to get workout routes for each workout (using its start and end date).
When providing a Predicate with time interval for a whole day, I got 4 saved workouts and 12 workout routes that couldn't be matched explicitly with each other (looking at metadata and timestamps).
Trying to get routes by providng the workout UUID returned the desired routes for each workout that I knew was saved by the third-party app.

Describe the solution you'd like
Add a function to pass workout UUID and get workout routes explicitly connected to this workout.

Describe alternatives you've considered
I tried subtracting a second from the start date and adding a second to the end date (as per some solutions I've found on the Internet), but it didn't give me any results.

Additional context

[karolinaoparczyk]

I've created a PR with this change: #79