Disable the search engine choice screen by default in Chrome

[Amoifr]

Q	A
Bug fix?	no
New feature?	yes
Deprecations?	no
Issues	Fix #636
License	MIT

Since Chrome 127, a search engine choice screen is shown on startup (mostly in the EU/EEA). It pops up in front of the page and blocks automated interactions, so Panther tests can fail with no obvious cause. The known workaround is to add --disable-search-engine-choice-screen to PANTHER_CHROME_ARGUMENTS.

As suggested by @dunglas in #636 ("we could even pass this flag by default"), this passes --disable-search-engine-choice-screen as a default Chrome argument, so it works out of the box. Users can still override the behavior through PANTHER_CHROME_ARGUMENTS if needed.

Note: the CHANGELOG.md currently stops at 2.3.0 while v2.4.0 is already tagged, so I added the entry under a new 2.5.0 section, feel free to adjust the version heading to match your release plan.

Thanks @Chris53897 for finding the flag, and @dunglas for the go-ahead! 🙏