Some updates to improve the performance of `LatticeOfCongruences` and friends#884

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james-d-mitchell merged 1 commit intosemigroups:mainfrom james-d-mitchell:sims1/faster-joins-latest

Mar 16, 2023

+1,100-422

Commits on Mar 16, 2023

conglatt: improve congruence lattice code
james-d-mitchell
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