"Among other provisions affecting insurance, the Act mandates that the ACA's risk corridor program be budget neutral.... A second insurance-related provision amends section 833 of the Internal Revenue Code, which grants tax benefits to Blue Cross and Blue Shield plans, as well as certain other qualifying health care organizations.... The Act's amendment aligns section 833's MLR definition with that provided by section 2718 of the ACA, pursuant to which costs associated with activities to improve health care quality may be counted in the numerator alongside medical claims."