refactor(licenses): Add validation to license requests and code refactor

[deo002]

Changes

• Add validation to License APIs(i.e. rf_risk value should be from 0-5,set some values that are required, do not allow empty strings for rf_shortname, rf_fullname etc)
• Code refactor:
  • Simplify code by using pointer values for struct fields of LicenseDB and LicenseUpdateJSONSchema. Previously, the reason for using generics such as OptionalData was to differentiate between actual zero values and undefined values in json(for datatypes such as bool, on parsing json, the value is populated as false(zero value) for both the cases in struct). Now, the default value will be nil for undefined and false when value is actually false. This will help in eliminating OptionalData and NullableAndOptionalData wrappers from codebase. No more need of using maps for updates and validation can be done in BeforeSave hook(hooks do not run for maps in GORM).
  • Reuse LicenseDB struct for Import, POST and Export and remove the redundant data types used for them.

Submitter Checklist

• Includes tests (if there is a feature changed/added)
• Includes docs ( if changes are user facing)
• I have tested my changes locally.

References

[GMishx]

Changes looks good.

[GMishx]

Changes looks good.

Tested, working as expected.