Fix input assuming the last character being a '\n'

Author: Virv12

Python/bltinmodule.c

@@ -2586,7 +2586,8 @@ builtin_input_impl(PyObject *module, PyObject *prompt)
                 result = NULL;
             }
             else {
-                len--;   /* strip trailing '\n' */
+                if (s[len-1] == '\n')
+                    len--;   /* strip trailing '\n' */
                 if (len != 0 && s[len-1] == '\r')
                     len--;   /* strip trailing '\r' */
                 result = PyUnicode_Decode(s, len, stdin_encoding_str,