Update pyarrow requirement from <16 to <19

Updates the requirements on [pyarrow](https://github.com/apache/arrow) to permit the latest version.
- [Release notes](https://github.com/apache/arrow/releases)
- [Commits](apache/arrow@apache-arrow-0.1.0...apache-arrow-18.0.0)

---
updated-dependencies:
- dependency-name: pyarrow
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

pyproject.toml

@@ -24,7 +24,7 @@ dependencies = [
   "packaging",              # compare versions of hydromt
   "pandas",                 # Dataframes
   "pooch",                  # data fetching
-  "pyarrow<16",             # prevents incompat with pandas.
+  "pyarrow<19",             # prevents incompat with pandas.
   "pydantic~=2.4",          # Validation
   "pydantic-settings~=2.2", # Settings Management
   "pyflwdir>=0.5.4",        # Hight models and derivatives