[pull] main from microsoft:main - #798

the TS overloads make it so that `options` is only set when `optionsOrEndpoint` is a string

otherwise, `optionsOrEndpoint` is the options object

)

some servers send lowercase headers, so allow for them (and any other casing) by always lowercasing before lookup

`_handleRequest` already records every request (and `_handleResponse` does not re-add it)

…lls (#41480)

`pollAgainstDeadline` mutates the provided `pollIntervals`

both `expect.poll` and `expect.toPass` pass it by reference

the former uses a per-test config, whereas the latter uses a per-project config that's shared by every test (in that worker)

…arts with ".." (#41475)

…umber">` (#41485)

see <https://w3c.github.io/html-aam/#accname-computation>

… or `/.../y` (#41470)

global `/.../g` and sticky `/.../y` regular expressions silently adjust `lastIndex`

this means that subsequent uses will miss any matches before the new `lastIndex` (until it wraps around)

as such, we should reset the `lastIndex` before trying to use it