Refactoring

- Slightly refactored sim_runner/core/runner.py:
  - use f-strings
  - fix trailing whitespaces
  - add conformity to PEP8 in:
    - naming
    - variable- and operator- related whitespaces allocation
- Fixed few warning from linter
- Added linter option to extend maximum line length to 120 symbols
  - default 80 symbols is way too short
14 jobs for feature/38-for-MC-production in 19 minutes and 16 seconds (queued for 6 seconds)