BUG: incorrect LaTeX typesetting in ylabel for fractions

[neutrinoceros]

Bug report

Bug summary

Just noticed this in some image reference used for testing:

The bug is that parenthesis should be bigger around a fraction. This is very similar to a bug that was fixed in #3282, but apparently we missed some cases.

[neutrinoceros]

So I thought the issue was in ProfilePlot but I can't reproduce the bug with the following script

import yt

ds = yt.load_sample("IsolatedGalaxy/galaxy0030/galaxy0030")
sphere = ds.sphere("c", (100.0, "kpc"))
plot = yt.ProfilePlot(
    sphere,
    ("gas", "temperature"),
    ("gas", "density"),
    weight_field=("gas", "mass"),
)
plot.save("/tmp/profile_test.png")

[neutrinoceros]

indeed the failing plot is of class LinePlot, not ProfilePlot.
Here's a reproducer:

import yt
ds = yt.load_sample("IsolatedGalaxy")
plot = yt.LinePlot(
    ds,
    [("gas", "density")],
    (0.0, 0.0, 0.0), (0.0, 1.0, 0.0), 1000
)

plot.save("/tmp/lineplot_test.png", mpl_kwargs=dict(bbox_inches="tight"))