Example t8_example_geometries.cxx is not working as expected

[lenaploetzke]

Bug report

Describe the bug
When I run the geometry example, e.g., for geometry number 0 (T8_GEOM_SINCOS), i get the error

[t8] Creating uniform level 2 forest with a sinus/cosinus geometry.
[t8 0] Constructed the geometry_handler.
[t8 0] Registering geometry with name t8_sincos_geometry
[t8 0] Cmesh is not partitioned.
[t8 0] committed cmesh with 2 local and 2 global trees and 0 ghosts.
[t8 0] t8_geometry_sincos is not compatible with tree type Hex
 It is only compatible with quad elements.
[t8 0] Detected incompatible geometry for tree 0

This surprises me in particular because the tree class is set to Quad in lines 695f.
Comparable errors are thrown when I call the example with other geometries.

To Reproduce
For example with
./t8_example_geometries -l 2 -g 0

Estimated priority
"Priority: medium" Should be solved within half a year

[holke]

@sandro-elsweijer
i have a feeling this might be related to when we dropped the dimension parameter from the geometry and made geometries valid for all dimensions.

[sandro-elsweijer]

@holke Yes its from that pr but that is not the reason, since the dimension member variable was never checked or used after being set

[sandro-elsweijer]

I can take a look at this after my holiday :)