refactor: rename testbench to test.

- rename testbench to test.
- add benchmark for future development.

test/yycc/macro/stl_detector.cpp

@@ -0,0 +1,20 @@
+#include <gtest/gtest.h>
+#include <yycc.hpp>
+#include <yycc/macro/stl_detector.hpp>
+
+#define STL ::yycc::macro::stl
+
+namespace yycctest::macro::stl {
+
+    TEST(MacroStl, Main) {
+        auto rv = STL::get_stl();
+#if defined(YYCC_STL_MSSTL)
+        EXPECT_EQ(rv, STL::StlKind::MsStl);
+#elif defined(YYCC_STL_GNUSTL)
+        EXPECT_EQ(rv, STL::StlKind::GnuStl);
+#else
+        EXPECT_EQ(rv, STL::StlKind::ClangStl);
+#endif
+    }
+
+} // namespace yycctest::macro::stl