[docs] [issue39096] "Format Specification Mini-Language" doc mistake for Decimal

Change by Mark Dickinson <dickinsm@gmail.com>: ---------- pull_requests: +22455 pull_request: https://github.com/python/cpython/pull/23575 _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue39096> _______________________________________