Werk #12978: Fix "User guide" link in "User" menu

Component	User interface
Title	Fix "User guide" link in "User" menu
Date	Jul 14, 2021
Level	Trivial Change
Class	Bug Fix
Compatibility	Compatible - no manual interaction needed
Checkmk versions & editions	2.0.0p8 Checkmk Community, Checkmk Pro, Checkmk Ultimate MT

The link led to an 404 error page.

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