sagemathgh-36124: fix cardinality, sagemath#36119, sagemath#36118, sa…

…gemath#36116

    
* Fix a thinko in the iterator for TSSCPP
* make plane partitions hashable
* avoid rational numbers in the cardinality methods, when necessary
* raise an error when an integer and a symmetry is provided as argument
to `PlanePartitions`

Fixes sagemath#36119
Fixes sagemath#36118
Fixes sagemath#36116

- [X] The title is concise, informative, and self-explanatory.
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- [X] I have created tests covering the changes.
    
URL: sagemath#36124
Reported by: Martin Rubey
Reviewer(s): Frédéric Chapoton