BigInt NumericValue definition missing exponent

[apsillers]

ES2020 defines the value of a parsed BigInt token in 11.8.3.2 as

1. Let n be the mathematical integer number of code points in DecimalDigits.
2. Let mv be (the MV of NonZeroDigit × 10_ℝⁿ) plus the MV of DecimalDigits.

ES2021 erroneously dropped the n exponent in 12.8.3.2, and it is missing in the current draft:

1. Let n be the number of code points in DecimalDigits, excluding all occurrences of NumericLiteralSeparator.
2. Let mv be (the MV of NonZeroDigit × 10) plus the MV of DecimalDigits.

[jmdyck]

Change occurred in PR #2007 (at this line).

The point was presumably to remove just the <sub>ℝ</sub>, but the <sup>_n_</sup> also got deleted.