Integrate coloured draw_tree visuals including on OpenSpiel notebook

[edwardchalstrey1]

Issues closed by this PR

• Closes [Tutorial]: Update OpenSpiel tutorial to include draw_tree #678

Description of the changes in this PR

This PR updates the draw_tree version to 0.3.1 where I have made changes that make sensible visualisation of the "Tiny Hanabi" game from the OpenSpiel notebook possible. A key new feature is colouring the extensive form tree by players, using a colour scheme similar to the Gambit GUI for now (which we can easily modify) and a legend, which de-clutters larger games substantially. I also updated stripped down poker to use the new colour scheme (didn't really add much to trust game in tutorial 2 so I haven't added it there).

How to review this PR

• Check out how the notebooks look now with ReviewNB link below
• Make sure the Tiny Hanabi game looks good rendered on the docs page

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[edwardchalstrey1]

The image renders very small on the doc so I will leave this as a draft and revisit in the new year: https://gambitproject--719.org.readthedocs.build/en/719/tutorials/interoperability_tutorials/openspiel.html

Edit: Though the user has to zoom in, we decided this is acceptable for the rendered doc

[edwardchalstrey1]

TODO:

• Remove the trailing 0's in the tiny hanabi 0.5 example