Fix Title in Book Detail View

[jessicaawhy]

Description

This change fixes a typo in the templating. It currently shows the title of the book twice.

I changed the template so it shows Title instead like the screenshot in the tutorial.
https://developer.mozilla.org/en-US/docs/Learn/Server-side/Express_Nodejs/Displaying_data/Book_detail_page/locallibary_express_book_detail.png

Summary of Changes

Changed #{title}: #{book.title} to Title: #{book.title}

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[hamishwillee]

Thanks very much @jessicaawhy - you're absolutely right.