Remove a duplicate.

01.curriculum/01.physics-chemistry-biology/01.Niv1/frontmatter.yaml

-# This page configuration is shared by all locales, in this directory.
-# You can override it in the individual frontmatter of the pages.
-
-content:
-    # https://learn.getgrav.org/15/content/collections#summary-of-collection-options
-    items: @self.children
-
-anchors:
-    active: false
\ No newline at end of file

01.curriculum/01.physics-chemistry-biology/01.Niv1/topic.es.md

----
-title: llanuras
-media_order: sesituersynt_400_2400.jpg
----
-

01.curriculum/01.physics-chemistry-biology/01.Niv1/topic.fr.md

----
-title: plaines
----
-