Missing Update operation for WFS layers without geometry

[gisuser0]

What is the bug or the crash?

Only Query, Insert and Delete are allowed for WFS layers without geometry. The Update operation is not available.

Steps to reproduce the issue

1. load any table without geometry into a QGIS project and enable all the WFS capabilities: Insert, Update and Delete (Project -> Properties -> QGIS Server -> WFS/OAPIF tab)
2. publish the project with QGIS-Server
3. Query, Insert and Delete are listed in the Operations of the WFS getCapabilities but Update is missing
4. open the layer with a WFS client (e.g. QGIS Desktop) and try to edit it: you can query, create and delete features but you can't update them

Versions

3.34.14 LTR (Windows and Linux)
3.40.2 (Windows and Linux)

Supported QGIS version

• I'm running a supported QGIS version according to the roadmap.

New profile

• I tried with a new QGIS profile

Additional context

Looking into the code it seems like the Update operation always requires the change geometry capability (Qgis::VectorProviderCapability::ChangeGeometries)