Update Arrow so that ArcticDB can be compiled with Clang 19 (#2134)

#### Reference Issues/PRs
<!--Example: Fixes #1234. See also #3456.-->
Arrow is used only in the C++ tests to make sure that our custom Decimal
implementation matches Arrow's. Current version of Arrow is 14 but that
doesn't compile with Clang 19.
#### What does this implement or fix?

#### Any other comments?

#### Checklist

<details>
  <summary>
   Checklist for code changes...
  </summary>
 
- [ ] Have you updated the relevant docstrings, documentation and
copyright notice?
- [ ] Is this contribution tested against [all ArcticDB's
features](../docs/mkdocs/docs/technical/contributing.md)?
- [ ] Do all exceptions introduced raise appropriate [error
messages](https://docs.arcticdb.io/error_messages/)?
 - [ ] Are API changes highlighted in the PR description?
- [ ] Is the PR labelled as enhancement or bug so it appears in
autogenerated release notes?
</details>

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cpp/vcpkg.json

@@ -108,6 +108,7 @@
   ],
   "overrides": [
     { "name": "openssl", "version-string": "3.3.0" },
+    { "name": "arrow", "version": "18.0.0" },
     { "name": "aws-sdk-cpp", "version": "1.11.474" },
     { "name": "azure-core-cpp", "version": "1.12.0" },
     { "name": "benchmark", "version": "1.9.0" },

environment_unix.yml

@@ -52,7 +52,7 @@ dependencies:
   - libiconv
   - aws-c-s3
   # Build dependencies for tests
-  - libarrow
+  - libarrow==18.0.0
   # Python dependences
   # Python 3.13+ is not yet supported
   - python <3.13