chore(deps): update pyarrow requirement

---
updated-dependencies:
- dependency-name: pyarrow
  dependency-version: 20.0.0
  dependency-type: direct:production
  dependency-group: production-dependencies
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

pyproject.toml

@@ -26,7 +26,7 @@ dependencies = [
     "pyarrow>=18.0.0,<21.0.0 ; sys_platform != 'darwin' or platform_machine != 'x86_64'",
     # pyarrow 18 causes macos build failures
     # https://github.com/ray-project/ray/pull/48446
-    "pyarrow>=8.0.0,<18.0.0 ; sys_platform == 'darwin' and platform_machine == 'x86_64'",
+    "pyarrow>=8.0.0,<21.0.0 ; sys_platform == 'darwin' and platform_machine == 'x86_64'",
     "typing-extensions>=4.4.0,<5",
     "packaging>=21.1,<26.0",
     "setuptools ; python_version >= '3.12'",