minor fixes after the rebase

Author: MaksymMalicki

rpc/mocks/mock_gateway_handler.go

@@ -219,7 +219,7 @@ func getClassProof(tr core.CommonTrie, classes []felt.Felt) ([]*HashToNode, erro
 	case *trie.Trie:
 		classProof := trie.NewProofNodeSet()
 		for _, class := range classes {
-			if err := (*trie.Trie)(t).Prove(&class, classProof); err != nil {
+			if err := t.Prove(&class, classProof); err != nil {
 				return nil, err
 			}
 		}
@@ -261,6 +261,7 @@ func buildContractLeavesData(
 	contractNotFoundErr error,
 ) ([]*LeafData, error) {
 	contractLeavesData := make([]*LeafData, len(contracts))
+
 	for i, contract := range contracts {
 		root, err := getRoot()
 		if err != nil {