Fix capitalization of Bilby

Description

Fix capitalization of Bilby

Fixes #340.

Checklist

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Changes:

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Grammar and spelling:

• I proofread my contribution and made sure that it is free from spelling and grammatical errors.
• I used American English rather than British English spelling.
• I used the Oxford (serial) comma in lists of three or more items.
• I minimized use of the passive voice.

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