Place trivet in bottom of Instant Pot insert.
Pour in chicken broth. Place onions, garlic and celery in bottom of Instant Pot.
In small bowl, mix together olive oil with paprika, rosemary, sage, thyme, salt and pepper.
Wash the turkey breast, remove gravy packet and pat dry.
Rub or brush the spice mixture onto the turkey breast, making sure to cover the whole thing as much as possible.
Put lid on Instant Pot, close valve and set timer for 35 minutes on Manual/Pressure Cook, high pressure.
Natural release pressure (which means wait until the pin drops on the valve and all pressure has released).
Remove turkey from pressure cooker.
Measure out 2 cups of liquid from the Instant Pot, being sure to strain any chunks.
Remove all remaining liquid and/or turkey pieces from Instant Pot and put the 2 cups that you had removed back in.
Mix together 2 tablespoons of cornstarch with 1/4 cup cold water.
Turn Instant Pot on Saute.
Pour mixture in slowly and cook until gravy thickens.
Slice turkey breast and serve with gravy served over the top.