Apply security patch 357-202503311017.patch (#104490)
* Sanitize paths before evaluating access to route
* use util.CleanRelativePath
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Co-authored-by: Andres Martinez Gotor <andres.martinez@grafana.com>
(cherry picked from commit 1f707d16ed)
Co-authored-by: Yuri Tseretyan <yuriy.tseretyan@grafana.com>