README example 1 error at `pytable(iris)`

**Affects:** PythonCall

**Describe the bug**
Running Pluto notebook and attempting to reproduce Example 1 in the README. `pytable(iris)` errors with:
`Python: Julia: ArgumentError: Unordered CategoricalValue objects cannot be tested for order using <. Use isless instead, or call the ordered! function on the parent array to change this`

**Your system**
Ubuntu 25.10
Pluto v1.0.1

Pkg.status() ***
[992eb4ea] CondaPkg v0.2.36
[6099a3de] PythonCall v0.9.35
[ce6b1742] RDatasets v0.8.1
[44cfe95a] Pkg v1.12.1

CondaPkg.status() ***
seaborn v0.13.2

perhaps a known issue related to issue #88

line reference:
https://github.com/JuliaPy/PythonCall.jl/blob/e477d4d805f5136c274576cc37cea6101bebe4c5/examples/seaborn.jl#L20

Start by reproducing README Example 1 in a Pluto notebook and inspect examples/seaborn.jl at line 20, where pytable(iris) is called. Confirm the reported CategoricalValue error with the listed environment. Done means the README example runs successfully without this error.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.