Remove link to numfocus for funding. (#1320)

Author: Carreau

pyproject.toml

@@ -38,7 +38,6 @@ dependencies = [
 [project.urls]
 Homepage = "https://ipython.org"
 Documentation = "https://ipykernel.readthedocs.io"
-Funding = "https://numfocus.org/donate"
 Source = "https://github.com/ipython/ipykernel"
 Tracker = "https://github.com/ipython/ipykernel/issues"