PhasePlot set_title() fails on ambiguous fields even when fully specified

[chummels]

Bug report

Bug summary

Plot annotation set_title() fails when the associated PhasePlot has a field which may be ambiguous, even if you specify the full field name.

Code for reproduction

import yt
ds = yt.load_sample('FIRE_M12i_ref11')
p = yt.PhasePlot(ds, ('gas', 'density'), ('gas', 'temperature'), [('gas', 'z')], weight_field=None)
p.annotate_title('test')
p.save()

Notice that the z field is fully specified as ('gas', 'z'), but yt gets unhappy because there are other z fields.

Actual outcome

Traceback (most recent call last):
  File "/Users/chummels/scratch/test_phase.py", line 4, in <module>
    p.annotate_title('test')
  File "/Users/chummels/src/yt/yt/visualization/_commons.py", line 112, in newfunc
    retv = f(self, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/chummels/src/yt/yt/visualization/profile_plotter.py", line 1324, in annotate_title
    self.plot_title[self.data_source._determine_fields(f)[0]] = title
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/chummels/src/yt/yt/data_objects/data_containers.py", line 1471, in _determine_fields
    finfo = self.ds._get_field_info(field)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/chummels/src/yt/yt/data_objects/static_output.py", line 1001, in _get_field_info
    raise ValueError(
ValueError: The requested field name 'z' is ambiguous and corresponds to any one of the following field types:
 ['index', 'gas', 'PartType0']
Please specify the requested field as an explicit tuple (<ftype>, <fname>).

Expected outcome

It should just work and generate a PhasePlot.