Issue-1858 Consider classificationCode from subject while inserting xml

[ashwinisukale]

Purpose

classificationCode was missing when we create XML from dois data.

closes: https://github.com/datacite/datacite/issues/1858

Approach

• Added byebug gem in development env in the gemspec
• Preserve the classificationCode when we see the data as xml
• Updated the vcr with new response which has classificationCode in the doi

Open Questions and Pre-Merge TODOs

Learning

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)

• [ ] New feature (non-breaking change which adds functionality)

• [ ] Breaking change (fix or feature that would cause existing functionality to change)

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