New way to identify THEORY_LEMMA clusters when printing in the .dot format (#8745)

New way to identify THEORY_LEMMA clusters when printing in the .dot format (#8745)

Change the way cvc5 identifies THEORY_LEMMA clusters when --print-dot-clusters option is used. Previously, only proof nodes with SCOPE rule after a CNF cluster could identify a THEORY_LEMMA cluster. Now, any of the following rules, after a CNF cluster, can identify it:

1. SCOPE
2. THEORY_LEMMA
3. Any rule R in the following range: CNF_ITE_NEG3 < R < LFSC_RULE

Signed-off-by: Vinícius Braga Freire vinicius.braga.freire@gmail.com