fixed backend test compilation

test/backends/QueryFixture.cpp

@@ -1,6 +1,8 @@
 #include "QueryFixture.hpp"
 
-#include "matador/sql/query.hpp"
+#include "matador/query/query.hpp"
+
+#include "matador/sql/dialect.hpp"
 
 #include "catch2/catch_test_macros.hpp"
 
@@ -10,7 +12,7 @@ QueryFixture::QueryFixture()
   : db(connection::dns)
   , schema(db.dialect().default_schema_name())
 {
-  db.open();
+  REQUIRE(db.open());
 }
 
 QueryFixture::~QueryFixture() {
@@ -37,7 +39,7 @@ void QueryFixture::check_table_not_exists(const std::string &table_name) const
 void QueryFixture::drop_table_if_exists(const std::string &table_name) const {
   const auto result = db.exists(table_name).and_then([&table_name, this](bool exists) {
     if (exists) {
-      if (sql::query::drop()
+      if (query::query::drop()
       .table(table_name)
       .execute(db).is_ok()) {
         this->check_table_not_exists(table_name);