Update netcdf4 requirement from >=1.7.1 to >=1.7.4

Updates the requirements on [netcdf4](https://github.com/Unidata/netcdf4-python) to permit the latest version.
- [Release notes](https://github.com/Unidata/netcdf4-python/releases)
- [Changelog](https://github.com/Unidata/netcdf4-python/blob/master/Changelog)
- [Commits](https://github.com/Unidata/netcdf4-python/commits)

---
updated-dependencies:
- dependency-name: netcdf4
  dependency-version: 1.7.4
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements.txt

@@ -1,7 +1,7 @@
 Jinja2>=3.1.4
 numpy>=2.0.0
 scipy>=1.14.1
-netcdf4>=1.7.1
+netcdf4>=1.7.4
 matplotlib>=3.7.0
 Cython>=3.0.0
 boutdata>=0.3.0