remove non-asci from data objects

[maxheld83]

currently, some of the data objects, and by extension, code include stuff like SCOAP<sup>3</sup> or SCOAP³.

This makes the package unportable and causes a WARNING in R CMD check.

Currently, the warning is simple allowed in the CI, but that's not really a good solution.

As part of the ETL refactoring, all data entries should be asci.

[maxheld83]

mmh, not sure about this. Just found out that using utf-escapes \uxxxx does get rid of the R CMD check error, but shiny does not appear to understand utf escapes, and then prints them literally.

Maybe just stick with the warning then.