Report of unique role types

[mcritchlow]

Descriptive summary

This is a follow up request related to #634 where it was noticed that we have roles in our metadata that are inconsistent in relation to case. As a workaround, we have code in place that is testing for capitalized and lowercased roles, but it was agreed that this should be fixed in the metadata itself.

request from @arwenhutt

a report with all unique role values (role ark, authoritative label value) would be great - thanks!

As a follow up to this, we should ideally remove the extraneous code this is checking for capitalized roles.

Rationale

Provide the rationale or user story that describes "why" this issue should be addressed. Especially if this is a new feature or significant change to the existing implementation.

Expected behavior

All roles are lowercased and duplicates are resolved.

Actual behavior

We have (duplicate) roles with mixed-case values, such as creator and Creator

Related work

#634
#672
#664