chore(deps): update dependency pyarrow to v18 (#1345)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [pyarrow](https://redirect.github.com/apache/arrow) | `15.0.2` ->
`18.0.0` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/pyarrow/18.0.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/pypi/pyarrow/18.0.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/pypi/pyarrow/15.0.2/18.0.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/pyarrow/15.0.2/18.0.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

> [!WARNING]
> Some dependencies could not be looked up. Check the warning logs for
more information.

---

### Release Notes

<details>
<summary>apache/arrow (pyarrow)</summary>

###
[`v18.0.0`](https://redirect.github.com/apache/arrow/releases/tag/apache-arrow-18.0.0):
Apache Arrow 18.0.0

Release Notes URL: https://arrow.apache.org/release/18.0.0.html

###
[`v16.1.0`](https://redirect.github.com/apache/arrow/compare/apache-arrow-16.0.0...apache-arrow-16.1.0)

###
[`v16.0.0`](https://redirect.github.com/apache/arrow/compare/apache-arrow-15.0.2...apache-arrow-16.0.0)

</details>

---

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gemini/sample-apps/llamaindex-rag/pyproject.toml

@@ -187,7 +187,7 @@ prometheus-client = "0.21.0"
 proto-plus = "1.24.0"
 protobuf = "4.25.5"
 ptyprocess = "0.7.0"
-pyarrow = "15.0.2"
+pyarrow = "18.0.0"
 pyarrow-hotfix = "0.6"
 pyasn1 = "0.6.1"
 pyasn1-modules = "0.4.1"