Fix intDiv

Essential fix based on [thread suggestion](duckdb/community-extensions#43 (review))

Author: lmangani

src/chsql_extension.cpp

@@ -68,7 +68,7 @@ static DefaultMacro chsql_macros[] = {
     {DEFAULT_SCHEMA, "toFloatOrNull", {"x", nullptr}, R"(TRY_CAST(x AS DOUBLE))"},
     {DEFAULT_SCHEMA, "toFloatOrZero", {"x", nullptr}, R"(CASE WHEN TRY_CAST(x AS DOUBLE) IS NOT NULL THEN CAST(x AS DOUBLE) ELSE 0 END)"},
     // -- Arithmetic macros
-    {DEFAULT_SCHEMA, "intDiv", {"a", "b"}, R"((CAST(a AS BIGINT) / CAST(b AS BIGINT)))"},
+    {DEFAULT_SCHEMA, "intDiv", {"a", "b"}, R"((CAST(a AS BIGINT) // CAST(b AS BIGINT)))"},
     // -- String matching macros
     {DEFAULT_SCHEMA, "match", {"string", "token"}, R"(string LIKE token)"},
     // -- Array macros