INQUIRER STAFF WRITERThe Bridgeport nanny standing trial for killing an infant 20 years ago on Tuesday waived her right to have the court consider her offense under a lesser legal standard for homicide. With jurors out of hearing, Melissa Haskell, 38, who is charged with third-degree felony murder, told Montgomery County Judge Garrett D. Page that she did not wish to have the charge downgraded to involuntary manslaughter.