Pin numpy in various stubs (#12554)

stubs/seaborn/METADATA.toml

@@ -1,6 +1,8 @@
 version = "0.13.2"
 # Requires a version of numpy and matplotlib with a `py.typed` file
-requires = ["matplotlib>=3.8", "numpy>=1.20", "pandas-stubs"]
+# see https://github.com/python/typeshed/issues/12551
+# on why we need the upper bound for numpy
+requires = ["matplotlib>=3.8", "numpy>=1.20,<2.1.0", "pandas-stubs"]
 # matplotlib>=3.8 requires Python >=3.9
 requires_python = ">=3.9"
 upstream_repository = "https://github.com/mwaskom/seaborn"