docs: CSS modules class name reference fix (2lRF7)

[39digits]

Description

The image and the text showing the value of the Avatar key do not currently match in the Styling Gatsby documentation.

[m-allanson]

👀 nice find, thanks @39digits 👍

[gatsbot]

Holy buckets, @39digits — we just merged your PR to Gatsby! 💪💜

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