BUG: noisy warnings when setting a custom colorbar norm for fields with take_log=False

[neutrinoceros]

Bug report

Bug summary

The logger filters out immediate repetitions, but when 2 different warnings are hit in a loop, it can quickly get pretty noisy.
The class reponsible for handling colorbar norms (NormHandler) emits warnings when it receives a new constraint that forces dropping of previously set ones (this is by design and still desired). Now, this warning assumes all previous constraint were either set by the user or inherited from a previous rendering of the plot, but there's one place where this rule is violated and we set norm constraint internally ahead of rendering:

yt/yt/visualization/plot_window.py

Lines 258 to 264 in cfdf7ed

	if finfo.take_log is False:
	# take_log can be `None` so we explicitly compare against a boolean
	pnh.norm_type = Normalize
	else:
	# do nothing, the norm handler is responsible for
	# determining a viable norm, and defaults to LogNorm/SymLogNorm
	pass

Within the right conditions, this combination of factors generates a lot of noisy and frankly useless warnings.

Code for reproduction

import yt
from yt.testing import fake_amr_ds
from matplotlib.colors import SymLogNorm

yt.set_log_level("warning")
def fake_field(field, data):
    return data["Density"]

field = ("gas", "fake_density")
for _ in range(5):
    ds = fake_amr_ds()
    ds.add_field(
        field,
        function=fake_field,
        sampling_type="cell",
        take_log=False,
    )
    p = yt.SlicePlot(ds, "z", field)
    p.set_norm(field, SymLogNorm(linthresh=1, base=2))
    p.save("/tmp/")

Actual outcome

yt : [WARNING  ] 2023-06-12 17:38:17,408 Field ('gas', 'fake_density') was added without specifying units or dimensions, auto setting units to 'g/cm**3'
yt : [WARNING  ] 2023-06-12 17:38:17,927 Dropping norm constraints (norm_type=<class 'matplotlib.colors.Normalize'>)
yt : [WARNING  ] 2023-06-12 17:38:18,698 Field ('gas', 'fake_density') was added without specifying units or dimensions, auto setting units to 'g/cm**3'
yt : [WARNING  ] 2023-06-12 17:38:18,871 Dropping norm constraints (norm_type=<class 'matplotlib.colors.Normalize'>)
yt : [WARNING  ] 2023-06-12 17:38:19,472 Field ('gas', 'fake_density') was added without specifying units or dimensions, auto setting units to 'g/cm**3'
yt : [WARNING  ] 2023-06-12 17:38:19,707 Dropping norm constraints (norm_type=<class 'matplotlib.colors.Normalize'>)
yt : [WARNING  ] 2023-06-12 17:38:20,313 Field ('gas', 'fake_density') was added without specifying units or dimensions, auto setting units to 'g/cm**3'
yt : [WARNING  ] 2023-06-12 17:38:20,482 Dropping norm constraints (norm_type=<class 'matplotlib.colors.Normalize'>)
yt : [WARNING  ] 2023-06-12 17:38:21,079 Field ('gas', 'fake_density') was added without specifying units or dimensions, auto setting units to 'g/cm**3'
yt : [WARNING  ] 2023-06-12 17:38:21,308 Dropping norm constraints (norm_type=<class 'matplotlib.colors.Normalize'>)

Expected outcome

The log should be limited to the first warning

yt : [WARNING  ] 2023-06-12 17:38:17,408 Field ('gas', 'fake_density') was added without specifying units or dimensions, auto setting units to 'g/cm**3'

Version Information

• Operating System: macOS
• Python Version: 3.11.4
• yt version: 4.2.0
• Other Libraries (if applicable):

[neutrinoceros]

note that I previously reported this warning as undesired in #4448