Device OS name is not correct

It looks like the device OS name is [hardcoded](https://github.com/XCTestHTMLReport/XCTestHTMLReport/blob/fcaa4d6265e815a8861b4bbc634600d276922d4a/Sources/XCTestHTMLReportCore/HTML/device.html#L3) as iOS which is not always true (macOS, visionOS, etc.). So this value could be more accurate in the final HTML file rather than assuming it will always be iOS.