NodeJS Controllers : Fix code snippet function parameter

[foxane]

db.getAuthorById() will compare string to number Fixed using Number() on authorId

Because

db.getAuthorById() will compare string to number, resulting all request to /:authorId return 'Author not found' regardless the id

This PR

• Called Number() on db.getAuthorById()s argument

Issue

Closes #28956

Additional Information

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