PR: Add a global filter flag to settings

[jsbautista]

Part of spyder-ide/spyder#20868

[ccordoba12]

@jsbautista or @dalthviz, could you add a test for this? It could be as simple as building the namespace view with and without the filter on and checking that a specific variable is absent/present in each case.

[dalthviz]

Thanks @jsbautista for the work here! Left a small suggestion. Regarding the test, I think we can use as boilerplate the one at:

spyder-kernels/spyder_kernels/console/tests/test_console_kernel.py

Lines 277 to 289 in fd7a942

	def test_get_namespace_view(kernel):
	"""
	Test the namespace view of the kernel.
	"""
	execute = asyncio.run(kernel.do_execute('a = 1', True))
	nsview = repr(kernel.get_namespace_view())
	assert "'a':" in nsview
	assert "'type': 'int'" in nsview or "'type': u'int'" in nsview
	assert "'size': 1" in nsview
	assert "'view': '1'" in nsview
	assert "'numpy_type': 'Unknown'" in nsview
	assert "'python_type': 'int'" in nsview

If you have any question let me know!

[dalthviz]

Thanks @jsbautista ! LGTM 👍

[ccordoba12]

Looks good to me now, thanks @jsbautista for your work on this!

[ccordoba12]

@dalthviz, please squash-merge as soon as @jsbautista resolves your comment above.