assert_frame_equal's error is too verbose

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Description

I work with large datasets (100k rows), and when I test dataframes using assert_frame_equal, I find that the error message is overly verbose and does not show me where the error is. This is because the error message printed will print out both dataframes in whole.

import polars as pl
from polars.testing import assert_frame_equal
from copy import deepcopy

a = list(range(0,1000,2))
b = deepcopy(a)

a[0] = 4
b[-1] = 2000

df_a = pl.LazyFrame({
    "a": a
})

df_b = pl.LazyFrame({
    "a": b
})

assert_frame_equal(df_a, df_b)

Maybe we can limit the number of rows printed in the error message / ideally incorporate compare functionality from #14373.