sagemathgh-39285: add parameter immutable to some graph products in…

… `sage/graphs/generic_graph.py`

    
Following sagemath#39280 and discussions in sagemath#39177, we add parameter `immutable`
to some graph product operations defined in
`sage/graphs/generic_graph.py`:
- `cartesian_product`
- `tensor_product`
- `lexicographic_product`
- `strong_product`
- `disjunctive_product`


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URL: sagemath#39285
Reported by: David Coudert
Reviewer(s): David Coudert, Frédéric Chapoton