Remove numpy-related errors

Author: sarlinpe

tests/demo.errors.stderr.txt

@@ -1,10 +1,4 @@
 pybind11_stubgen - [  ERROR] In demo._bindings.aliases.foreign_enum_default : Invalid expression '<ConsoleForegroundColor.Blue: 34>'
-pybind11_stubgen - [  ERROR] In demo._bindings.eigen.dense_matrix_c : Can't find/import 'm'
-pybind11_stubgen - [  ERROR] In demo._bindings.eigen.dense_matrix_c : Can't find/import 'n'
-pybind11_stubgen - [  ERROR] In demo._bindings.eigen.dense_matrix_r : Can't find/import 'm'
-pybind11_stubgen - [  ERROR] In demo._bindings.eigen.dense_matrix_r : Can't find/import 'n'
-pybind11_stubgen - [  ERROR] In demo._bindings.eigen.four_col_matrix_r : Can't find/import 'm'
-pybind11_stubgen - [  ERROR] In demo._bindings.eigen.four_row_matrix_r : Can't find/import 'n'
 pybind11_stubgen - [  ERROR] In demo._bindings.enum.accept_defaulted_enum : Invalid expression '<ConsoleForegroundColor.None_: -1>'
 pybind11_stubgen - [  ERROR] In demo._bindings.flawed_bindings.accept_unbound_enum : Invalid expression '(anonymous namespace)::Enum'
 pybind11_stubgen - [  ERROR] In demo._bindings.flawed_bindings.accept_unbound_enum_defaulted : Invalid expression '<demo._bindings.flawed_bindings.Enum object at 0x1234abcd5678>'