"HeadlessChrome" appeared in the user-agent string of a headless UC browser

(This is a regression in seleniumbase 4.38.1)

"HeadlessChrome" is supposed to be replaced by just "Chrome" so that headless is more stealthy.

There may be more regressions related to this.
(There's an off-by-one issue related to passing Chrome options.)

This issue was caught by CI: https://github.com/mdmintz/seleniumbase-examples/actions/runs/14985542985.