Whisk soy sauce, rice vinegar, sesame oil, sambal oelek, sherry, and garlic together in a bowl. Pour sauce into a multi-functional pressure cooker (such as Instant Pot®). Set a steamer basket on top of the sauce and place broccoli inside the basket. Close and lock the lid. Select high pressure according to manufacturer's instructions; set timer for 0 minutes. Allow 10 to 15 minutes for pressure to build.