Unable to re-expand a collapsed page preview for a chapter #1643

Describe the bug
When expanding a chapters pages in the book view and re-collapsing it, one is not able to expand it again.

Steps To Reproduce
Steps to reproduce the behavior:

1. Go to '/books/foo' that has at least one chapter with pages in it
2. Click on 'x pages' to expand the page preview for the chapter
3. Click on 'x pages' to collapse the page preview for the chapter
4. When clicking on 'x pages' again, nothing happens

Expected behavior
One should be able to expand the pages list of that chapter again.

Screenshots

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Your Configuration (please complete the following information):

• Exact BookStack Version (Found in settings): BookStack v0.27.4 (lastest release)
• PHP Version: 7.2
• Hosting Method (Nginx/Apache/Docker): Docker behind Nginx reverse proxy

Additional context

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