repl: show exception for out-of-range unicode escape sequence
> '\u{10fffe}'
'???'
> '\u{10ffff}`
'???'
> '\u{110000}'
...
The REPL hangs waiting for completion because of the SyntaxError: Unexpected token ILLEGAL
exception.
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
> '\u{10fffe}'
'???'
> '\u{10ffff}`
'???'
> '\u{110000}'
...
The REPL hangs waiting for completion because of the SyntaxError: Unexpected token ILLEGAL
exception.