Add comment explaining the #[allow(dead_code)] on needed_proof_types in

ProofCoordinator: the field is used again in PR #6157 and is preserved
to simplify merge conflicts.

Author: avilagaston9

crates/l2/sequencer/proof_coordinator.rs

@@ -43,6 +43,7 @@ pub struct ProofCoordinator {
     rollup_store: StoreRollup,
     rpc_url: String,
     tdx_private_key: Option<SecretKey>,
+    // Used again in PR #6157; kept here to simplify merge conflicts.
     #[allow(dead_code)]
     needed_proof_types: Vec<ProverType>,
     aligned: bool,