Refactor internal/config package and have it checks the necessary config values

[yfei1]

This issue tracks the progress on refactoring the internal/config package. Our current config package directly read the config files from viper and wont check what fields are missing at all. It would be great if we could refactor/add a tool to check what fields are missing from the config and document the default config values for the optional fields instead.

[sawagh]

Would this be usage impacting? or just making Open Match more resilient to misconfigurations? If the later, we can move this to v0.10

[akremsa]

I can take a look at this one. @yfei1 @Laremere where can I check which values are mandatory or not? Some default value I've found here: https://open-match.dev/site/docs/installation/helm/#configuration