tools/tinytest-codegen.py: Add extra newline and result message.

This is an alternative to f4ed2df that adds a newline so that the output of
the test starts on a new line and the result of the test is prefixed with
"result: " to distinguish it from the test output.

Suggested-by: @dpgeorge

tools/tinytest-codegen.py

@@ -33,8 +33,10 @@ test_function = (
     "void {name}(void* data) {{\n"
     "  static const char pystr[] = {script};\n"
     "  static const char exp[] = {output};\n"
+    '  printf("\\n");\n'
     "  upytest_set_expected_output(exp, sizeof(exp) - 1);\n"
     "  upytest_execute_test(pystr);\n"
+    '  printf("result: ");\n'
     "}}"
 )