tests:Add new test for failing to load error_upper in h5 file

[smithsp]

This is an attempt to isolate https://github.com/gafusion/OMFIT-source/issues/6191 to an error in the omas library.
Mention @bechtt
This should fail on test_omas_core for test_load_error_upper:

======================================================================
ERROR: test_load_error_upper (omas.tests.test_omas_core.TestOmasCore)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/smithsp/omas/omas/tests/test_omas_core.py", line 420, in test_load_error_upper
    ods = load_omas_h5(f'{imas_json_dir}/../samples/ods_with_error_upper.h5')
  File "/home/smithsp/omas/omas/omas_h5.py", line 136, in load_omas_h5
    ods.consistency_check = consistency_check
  File "/home/smithsp/omas/omas/omas_core.py", line 645, in consistency_check
    self.getraw(item).consistency_check = consistency_value_propagate
  File "/home/smithsp/omas/omas/omas_core.py", line 645, in consistency_check
    self.getraw(item).consistency_check = consistency_value_propagate
  File "/home/smithsp/omas/omas/omas_core.py", line 645, in consistency_check
    self.getraw(item).consistency_check = consistency_value_propagate
  [Previous line repeated 3 more times]
  File "/home/smithsp/omas/omas/omas_core.py", line 629, in consistency_check
    value, txt = consistency_checker(location, self.getraw(item), info, consistency_value, self.imas_version)
  File "/home/smithsp/omas/omas/omas_core.py", line 138, in consistency_checker
    raise ValueError(txt)
ValueError: equilibrium.time_slice.0.constraints.bpol_probe.0.measured is of type <class 'numpy.ndarray'> must be a scalar of type FLT_0D

Note that when I started working, I was on the inhomo_multi_dim_time branch, specifically commit dbdcbb2 . I can run a git bisect if needed, but thought I would let @orso82 see if there was something easy that stands out first before I put in the effort.

[orso82]

Thank you @smithsp I'll take a look