CifToBddExprOnlySupportedExprsCheck: cache algebraic variable checks not only for predicates but also for int/enum-typed expressions

This is a follow-up to #1187 (closed). There we added caching in CifToBddExprOnlySupportedExprsCheck for checking of algebraic variables in predicates, but forgot to add caching for algebraic variables in int/enum-typed expressions. We should add that as well.