Documentation for lower bound

[Daniel-Packer]

Added ott.solvers.quadratic.lowerbound.LowerBoundSolver to the Gromov-Wasserstein Documentation.

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[michalk8]

@Daniel-Packer just a heads-up that @marcocuturi refactored the code #472 , so you might need to adjust the notebook a bit again.

[marcocuturi]

thanks @Daniel-Packer , as Michal was mentioning I refactored the univariate solvers code (and Michal also had an extra pass)

[michalk8]

Closing this, since the univariate solvers have been refactored again in #505

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Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.54%. Comparing base (f139415) to head (8ff9fb5).
Report is 89 commits behind head on main.

Additional details and impacted files

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  Misses        462      462           
  Partials      140      140