reword echo_char error message per suggestion

Co-authored-by: Bénédikt Tran <[email protected]>

Author: bkjoh

Lib/getpass.py

@@ -153,8 +153,8 @@ def _check_echo_char(echo_char):
             and echo_char.isprintable()
             and echo_char.isascii()
         ):
-        raise ValueError("'echo_char' must be a single-character, printable "
-                         f"ASCII string, got: {echo_char!r}")
+        raise ValueError("'echo_char' must be a single printable ASCII "
+                         f"character got: {echo_char!r}")
 
 
 def _raw_input(prompt="", stream=None, input=None, echo_char=None):