xoai.xml is not schema valid (wrong element order)

[saschaszott]

Description

This PR fixes some schema violations in xoai.xml (Filter elements are expected to occur before CustomCondition elements).

[saschaszott]

@jor4science, this is not production-critical but easy to merge.

[github-actions]

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[saschaszott]

@jor4science , do you have any updates on this issue?