Make numpy dependency from types-networkx optional

Author: tqa236

stubs/networkx/METADATA.toml

@@ -1,7 +1,5 @@
 version = "3.5"
 upstream_repository = "https://github.com/networkx/networkx"
-# requires a version of numpy with a `py.typed` file
-requires = ["numpy>=1.20"]
 # Uses more recent dataclass kwargs
 requires_python = ">=3.10"