[docs] [issue18894] In unittest.TestResult.failures remove deprecated fail* methods

[Terry J. Reedy]

Changes by Terry J. Reedy <tjreedy at udel.edu>:


----------
nosy: +ezio.melotti, michael.foord

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue18894>
_______________________________________