Autowire Converters in WebMVC

[GODrums]

Motivation

Seperating the server logic across dedicated files often helps keep files clean and understandable. Our type converters can easily be handled by Spring itself, making manual handling obsolete.

Description

This PR adds all our type converters to a dedicated WebMvcConfigurer making it possible to be autowired whenever necessary. This cleans up a lot of boilerplate code of our GitHubDataSyncService-constructor, letting Spring handle the injection.
Source: https://www.baeldung.com/spring-type-conversions#creating-a-custom-converter

Checklist

General

• PR title is clear and descriptive
• PR description explains the purpose and changes
• Code follows project coding standards
• Self-review of the code has been done
• Changes have been tested locally
• Screenshots have been attached (if applicable)
• Documentation has been updated (if applicable)

Server (if applicable)

• Code is performant and follows best practices
• No security vulnerabilities introduced
• Proper error handling has been implemented
• Added tests for new functionality
• Changes have been tested in different environments (if applicable)

[iam-flo]

Looks good to me!

[GODrums]

At some point we could probably think about using https://github.com/ronmamo/reflections to automatically detect these kinds of classes to generalize these configuration classes, also applying to ClassImportIntegratorIntegratorProvider.
@FelixTJDietrich, let me know if this is something you are interested in and I could integrate it into this PR already.

[FelixTJDietrich]

Looks good to me, i think it is fine like this for now. I guess we will have some more converters in the future for GitLab etc. but we can just add them here manually for now 👍