Cyclic dependencies

[mtelka]

Describe the bug

pipdeptree reports this:

------------------------------------------------------------------------
Warning!! Cyclic dependencies found:
* sphinxcontrib-applehelp => sphinx => sphinxcontrib-applehelp
* sphinxcontrib-devhelp => sphinx => sphinxcontrib-devhelp
* sphinxcontrib-htmlhelp => sphinx => sphinxcontrib-htmlhelp
* sphinxcontrib-qthelp => sphinx => sphinxcontrib-qthelp
* sphinxcontrib-serializinghtml => sphinx => sphinxcontrib-serializinghtml
* sphinx => sphinxcontrib-applehelp => sphinx
------------------------------------------------------------------------

I think this was introduced by recent releases of sphinxcontrib-* projects.

How to Reproduce

Run pipdeptree with installed latest version of sphinx.

Environment Information

NA

Sphinx extensions

No response

Additional context

No response

[picnixz]

This is something intended and discussed here #11567.