Refactor GitLab bot
- Use more methods for well-arranged structure
- Determine existing branches and merge requests via efficient requests
- Rename '_bot_project' to '_main_project'
- Rename 'old_providers_data' to 'old_provider_data'
- Rename 'new_providers_data' to 'new_provider_data'
- Determine updated providers without the need for each bot to provide them
Depends on !297 (merged)
Edited by Melvin Keskin