Fix Credetial -> Credential typo.

[alexmv]

Description

Fix a typo in the Config struct.

Checklist

• [x] Code compiles correctly
• [x] Created tests (if appropriate)
• [x] All tests passing
• [x] Extended the README / documentation (if necessary)

[dropwhile]

ha! Thanks for the fix. At least I was consistent in my misspelling. 😆