Update gdal requirement from ~=3.6.4 to ~=3.9.1

Updates the requirements on [gdal](https://github.com/OSGeo/gdal) to permit the latest version.
- [Release notes](https://github.com/OSGeo/gdal/releases)
- [Changelog](https://github.com/OSGeo/gdal/blob/v3.9.1/NEWS.md)
- [Commits](OSGeo/gdal@v3.6.4...v3.9.1)

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

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

requirements-pipeline.txt

@@ -4,5 +4,5 @@ dagster-docker==0.23.12
 geopandas==0.14.3
 GeoAlchemy2==0.14.4
 # Because a specific version of the PyPi GDAL package depends on specific OS library versions, and because Ubuntu (LTS) currently only provides *older* versions of them, we ping GDAL to v3.6 here.
-GDAL~=3.6.4
+GDAL~=3.9.1
 defusedxml==0.7.1