Trim any excess skin that stretches beyond the top of the chicken thighs. In a small bowl, combine the salt, pepper, paprika and Italian seasoning. Sprinkle all over both sides of the chicken thighs. Set your Instant Pot to the sauté setting and let the insert heat until very hot (it takes 2 to 3 minutes to heat up). Add the olive oil to the base of the pot, then 1/2 of the chicken thighs, skin-side down. Cook until golden brown, 5 to 7 minutes. Remove the thighs to a plate. Repeat with the remaining chicken thighs, then transfer to a plate. Turn off the Instant Pot. Add the garlic, lemon slices, and chicken stock to the pot. Scrape any browned bits from the bottom of the pot with a wooden spoon. Nestle the chicken thighs skin-side up in the pot (you may have to shingle them slightly). Cover the Instant Pot with the lid and lock into place. Seal the steam release handle. Select high pressure and set the timer for 15 minutes. When timer is up, let the pressure release naturally for 20 minutes, then manually release any remaining pressure. Remove the lid and transfer the thighs to a plate. Cover loosely with foil to keep warm. Discard the lemon slices and garlic and return the Instant pot to the sauté setting. In a small bowl, whisk together 2 tablespoons of water and the cornstarch. Add this to the pot and cook, whisking occasionally, until the mixture comes to a boil. Let simmer, whisking frequently, for 1 minute, until thickened. Turn off the Instant Pot. Season with more salt and pepper to taste. Serve the chicken with a drizzle of the sauce, topped with chopped fresh herbs.