Added a minimal test for Statement::getExtendedSQL()

- there is nothing conditional here in the wrapper

tests/Statement_test.cpp

@@ -252,6 +252,7 @@ TEST(Statement, bindings) {
         insert.bind(1, text);
         insert.bind(2, integer);
         insert.bind(3, dbl);
+        EXPECT_EQ(insert.getExtendedSQL(), "INSERT INTO test VALUES (NULL, 'first', -123, 0.123)");
         EXPECT_EQ(1, insert.exec());
         EXPECT_EQ(SQLITE_DONE, db.getErrorCode());