Choose special name to avoid '@c' by singular's absFactorize

[nbruin]

Fixes #33327

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⌛ Dependencies

[dimpase]

Are you sure "SAGE_ALGEBRAIC" won't pop up somewhere back in Sage data?
Otherwise looks good to me.

[nbruin]

No, it's obviously very doable to create examples that generate a SAGE_ALGEBRAIC identifier name, and introducing the name in the codebase certainly increases the probability of encountering it somewhere. However, the name should not escape from the internal qqbar routine here, so I think it's a definite improvement. If we end up running into examples with this name without people feeling they had it coming, we can write an adaptive name generation routine. The ring gets flattened, so getting an overview of the names involved should be quite doable. Presently I think it would be overengineering to do that.

[github-actions]

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[dimpase]

OK, fine.
I tried this kind of workaround, but I forgot an extra pair of ' ' and thought it's trickier than that. :-)