Update uarch detection

[jgphpc]

Motivation: #479

• Describe:

q-e-sirius_check_uenv.py has to call uenv image inspect to check the uarch of the uenv.
Maybe this could be done by ReFrame config/ci instead.

# beverin
uenv image pull q-e-sirius/v1.0.1:v1
error: more than one uenv found that matches 'q-e-sirius/v1.0.1:v1':
q-e-sirius/v1.0.1:v1  mi200  beverin  1ade9aefcdc82ec5   3,035    2025-12-03
q-e-sirius/v1.0.1:v1  mi300  beverin  43db5fda6c6a023c   4,014    2025-12-03

--> UENV=q-e-sirius/v1.0.1:v1%mi200,q-e-sirius/v1.0.1:v1%mi300

Not an issue with multiarch uenv:

uenv image find prgenv-gnu
uenv                        arch    system   id                size(MB)  date
prgenv-gnu/25.07-6.3.3:v12  amdgpu  beverin  b590e5227d7d4c02   5,295    2026-01-14

and config/systems/beverin.py has 2 partitions:

'name': 'mi200', 'features': ['uenv', ...]
'name': 'mi300', 'features': ['uenv', ...]

UENV=prgenv-gnu/25.07-6.3.3:v12 reframe -r ...
[ RUN      ]  @beverin:mi300+prgenv-gnu_25.07-6.3.3_v12_default
[ RUN      ]  @beverin:mi200+prgenv-gnu_25.07-6.3.3_v12_default

• Share the command line used to run the test

$ reframe -r ...