Update browser-access.adoc

[OlliTietavainenVaadin]

Added information about how to get the WebBrowser object

[github-actions]

AI Language Review

In the file "Browser Access":

1. The addition of the "Accessing Browser Information" section is a useful enhancement, but the example can be improved by explaining what "user-agent" means and how it is typically used in applications. Also, clarify what specific browsers and scenarios the checks for isWindows() and isChrome() address.

2. Ensure the phrasing in the new section matches the tone and level of detail used in the rest of the document, maintaining clarity and consistency.