Update dog breed names for en-US locale

[mononoken]

Motivation / Background

I started this PR from noticing data generated from Faker::Creature::Dog.breed had African as a dog breed. This is not a valid dog breed from searching online. There is a breed called Africanis, so I have updated this entry to that.

While updating this value, I noticed some other names that could be cleaned up such as Stbernard being updated to Saint Bernard. I also noted that the docs state to use dash syntax, so I formatted the file first so that it would be easy to follow the name changes.

Additional information

I used https://en.wikipedia.org/wiki/List_of_dog_breeds as a reference. I did not change every inconsistency compared to these wiki names. For example, "Irish Spaniel" is not an entry on the wiki. I mostly tried to target errors and typos.

Checklist

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• This Pull Request is related to one change. Changes that are unrelated should be opened in separate PRs.
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[thdaraujo]

nice, thank you!