fix: increase N_max in Zeromorph (#6415)

To avoid edge case in `batch_mul` of vanilla Ultra we temporarily
switched to naive muls in the folding recursive verifier circuit
arithmetised with Ultra which causes an increase by a factor of 2. Hence
we need to increase the maximum size of a circuit that can be proven
with Zeromorph.

barretenberg/cpp/src/barretenberg/commitment_schemes/zeromorph/zeromorph.hpp

@@ -41,7 +41,7 @@ template <typename PCS> class ZeroMorphProver_ {
 
     // TODO(#742): Set this N_max to be the number of G1 elements in the mocked zeromorph SRS once it's in place.
     // (Then, eventually, set it based on the real SRS). For now we set it to be large but more or less arbitrary.
-    static const size_t N_max = 1 << 22;
+    static const size_t N_max = 1 << 23;
 
   public:
     /**