Bump polars from 0.18.7 to 0.18.8 (#526)

Bumps [polars](https://github.com/pola-rs/polars) from 0.18.7 to 0.18.8.
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/pola-rs/polars/commit/05fa3448268b08e75092b665979220465b9ee8c5"><code>05fa344</code></a>
python polars 0.18.8 (<a
href="https://redirect.github.com/pola-rs/polars/issues/9989">#9989</a>)</li>
<li><a
href="https://github.com/pola-rs/polars/commit/90df2bc9c090c60f6776e84f8a24891ddfc8cb72"><code>90df2bc</code></a>
feat(python): Name transpose from column (<a
href="https://redirect.github.com/pola-rs/polars/issues/9846">#9846</a>)</li>
<li><a
href="https://github.com/pola-rs/polars/commit/b7f6c7a73365814730e1800f949c6b69259ae933"><code>b7f6c7a</code></a>
feat(rust,python): add use_earliest argument to truncate (<a
href="https://redirect.github.com/pola-rs/polars/issues/9899">#9899</a>)</li>
<li><a
href="https://github.com/pola-rs/polars/commit/a70ecbfc13e69336616ebedf6761a233b61349c1"><code>a70ecbf</code></a>
fix(rust, python): fix incorrect state in projection pushdown with joins
(<a
href="https://redirect.github.com/pola-rs/polars/issues/9987">#9987</a>)</li>
<li><a
href="https://github.com/pola-rs/polars/commit/980dac2452ed9af19c86b53c127d85b85aeb5549"><code>980dac2</code></a>
feat(python): adds <code>SQRT</code>, <code>CBRT</code>, <code>PI</code>
functions to <code>SQLContext</code> (<a
href="https://redirect.github.com/pola-rs/polars/issues/9936">#9936</a>)</li>
<li><a
href="https://github.com/pola-rs/polars/commit/3f34ad162f6b22ea7d62152e510db6001c9c15e6"><code>3f34ad1</code></a>
feat(rust, python): Let qcut create evenly spaced probabilities (<a
href="https://redirect.github.com/pola-rs/polars/issues/9960">#9960</a>)</li>
<li><a
href="https://github.com/pola-rs/polars/commit/52f6449457307f75fbbc2c2a6db41a936545ad34"><code>52f6449</code></a>
chore: Update autolabeler again (<a
href="https://redirect.github.com/pola-rs/polars/issues/9984">#9984</a>)</li>
<li><a
href="https://github.com/pola-rs/polars/commit/10f3c069f6e8df8cefe26019fec6276188bdc067"><code>10f3c06</code></a>
refactor(python): use original <code>Instruction</code> objects during
bytecode translat...</li>
<li><a
href="https://github.com/pola-rs/polars/commit/9ca9c2a4ada78e46a55a89a22b3ec8ef8076da99"><code>9ca9c2a</code></a>
feat(python): add freeze_panes option to write_excel (<a
href="https://redirect.github.com/pola-rs/polars/issues/9974">#9974</a>)</li>
<li><a
href="https://github.com/pola-rs/polars/commit/977d7e548e7f6039a467036a2d8692a8df477392"><code>977d7e5</code></a>
feat(python): initial support for parsing the set of <code>jump</code>
bytecode instruct...</li>
<li>Additional commits viewable in <a
href="https://github.com/pola-rs/polars/compare/py-0.18.7...py-0.18.8">compare
view</a></li>
</ul>
</details>
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</details>

Author: Marenz

pyproject.toml

@@ -54,7 +54,7 @@ dev-docstrings = [
   "darglint == 1.8.1",
   "tomli == 2.0.1",      # Needed by pydocstyle to read pyproject.toml
 ]
-dev-examples = ["polars == 0.18.7"]
+dev-examples = ["polars == 0.18.8"]
 dev-formatting = ["black == 23.7.0", "isort == 5.12.0"]
 dev-mkdocs = [
   "mike == 1.1.2",