Fix(49473): Added docs for RegExpMatchArray

[Grubba27]

Fixes #49473
The change broke some tests 😢
gulp runtests:

for some reason gulp baseline-accept & gulp baseline-accept-wrc does not update the lib package. Maybe I`m missing some gulp command in between ?
I ran gulp LKG but it updated ~ 92 files ~ I should have commited them ?

[DanielRosenwasser]

for some reason gulp baseline-accept & gulp baseline-accept-wrc does not update the lib package.

The baselines get generated in tests/baselines/local, and the baseline-accept command copies them into tests/baselines/reference. When you're ready, you need to stage them and commit them in git.

So the TL;DR is that you need to run:

gulp baseline-acept
git add tests/baselines/
git commit -m "Accepted baselines."

[DanielRosenwasser]

Looks like there are some baselines you missed since merging from main (promisePermutations, promisePermutations2, promisePermutations3, duplicateNumericIndexers).