Link containers on transcipt have large margins

[0x65-e]

#43 added margin-top: 1em to .link-container h3 to resolve spacing issues on the resume page. This introduced unintentional issues on the transcript page since course headers also use h3 elements inside link containers.

Possible solutions:

• Add CSS classes for h3 elements to indicate whether they should be spacing-adjusted or not
• Modify the macro for course listings to manually style the h3 elements

This same issue may crop up again for h4 elements in the future, since their spacing was also adjusted. To resolve these issues, the best approach is probably to create new CSS classes.