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

Change by Terry J. Reedy <tjreedy@udel.edu>: ---------- title: Description of "Format Specification Mini-Language" not accurate for Decimal -> "Format Specification Mini-Language" doc mistake for Decimal _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue39096> _______________________________________