Skip test_tstring.py from ruff

Author: lysnikolaou

Lib/test/.ruff.toml

@@ -7,6 +7,8 @@ extend-exclude = [
     # Failed to lint
     "encoded_modules/module_iso_8859_1.py",
     "encoded_modules/module_koi8_r.py",
+    # SyntaxError because of t-strings
+    "test_tstring.py",
     # TODO Fix: F811 Redefinition of unused name
     "test_buffer.py",
     "test_dataclasses/__init__.py",