Setup prettier for formatting

[hanefi]

We have an .editorconfig file that is not enforced. Here comes prettier to the rescue.

TODO:

• [x] Run prettier with the newly introduced configs
• [x] Make sure that .editorconfig rules are now enforced
• [ ] Add CI checks to run prettier
• [ ] Update docs
  • [ ] How to run prettier
  • [ ] How to fix tests if prettier tests fail