Improve dev environment

[Tumetsu]

Description of change

Add some improvements for local development and update some tools. Main changes are

• Bump from node 10 -> 16 to let use more modern JS syntax
• Update prettier to 2.x. Not strictly required but probably nicer for the future to have it up to date
• Add docker-compose to spin up Mongodb for local development. Hopefully this gives more clear and easy way to get local environment up and running for development.

Related issue

This is tangentially related to https://github.com/jaamo/strava2kilometrikisa/issues/64 since I basically created this for the basis of that change and my later effort to port the application to Typescript.

How has this been tested?

Local environment seems to work fine and lets me to log in to strava and Kilometrikisa. Naturally couldn't test in production yet since the Kilometrikisa 2022 has not started yet.

[Tumetsu]

Oops, just now I noticed that there is already a pending PR about Docker: https://github.com/jaamo/strava2kilometrikisa/pull/56 :sweat_smile:

However, I think that PR won't work with cron worker on local dev. Well, I can rebase these changes on top of that PR if needed.