pip prod(deps): update ipython requirement from <=8.27.0 to <=8.28.0

Updates the requirements on [ipython](https://github.com/ipython/ipython) to permit the latest version.
- [Release notes](https://github.com/ipython/ipython/releases)
- [Commits](ipython/ipython@5.0.0...8.28.0)

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

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

docs/requirements.txt

@@ -14,7 +14,7 @@ cftime # >=1.5.1
 cfgrib # >=0.9.9.1
 decorator
 distributed>=2.30.0
-ipython<=8.27.0
+ipython<=8.28.0
 matplotlib>=3.4.0
 numpy==1.26.4
 pandas<3.0