[vulnerability] dep fix
Fixes https://github.com/huggingface/transformers/security/dependabot/examples/research_projects/lxmert/requirements.txt/Pygments/open

@LysandreJik

Oh, is this process somehow automated and I didn't know about it? All I see is the file which it complains about and no suggestion to automate the fix.<|||||>Yeah, but usually it's not as good as your suggestion as it offers `==` while you offer `>=`.

I think I mentioned it here: https://github.com/huggingface/transformers/pull/10817

But thank you nonetheless, these are helpful!<|||||>Hmm, I have been copying exactly what the vulnerability bot suggested - which is always `>=` - so it's probably the dependabot that could use a bit of an update to match the vulnerability report.

But it's good to know that this is already automated, I will know not to make a PR next time.