Add test for NotReceived transaction status

Add unit test for GetTransaction RPC method handling the case when
feeder client returns starknet.NotReceived. The test verifies
that the error is properly propagated as errTransactionNotFound

rpc/transaction_test.go

@@ -1281,6 +1281,17 @@ func TestTransactionStatus(t *testing.T) {
 				require.NotNil(t, err)
 				require.Equal(t, err, rpc.ErrTxnHashNotFound)
 			})
+
+			t.Run("not received", func(t *testing.T) {
+				mockReader := mocks.NewMockReader(mockCtrl)
+				notReceivedHash := test.notFoundTxHash
+
+				mockReader.EXPECT().TransactionByHash(notReceivedHash).Return(nil, db.ErrKeyNotFound)
+
+				handler := rpc.New(mockReader, nil, nil, "", log).WithFeeder(client)
+				_, err := handler.TransactionStatus(ctx, *notReceivedHash)
+				require.Equal(t, rpc.ErrTxnHashNotFound, err)
+			})
 		})
 	}
 }