website: Adjust embedded video resolution ratio and add max-width

* Increase the height embedded video iframe's. This makes the
content of the video clearer.
* Embedded videos could become too wide on wide screen, the
max-width property is added to prevent the iframe from becoming
too wide.

Signed-off-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Change-Id: I8e001be9fa92b4e0b585e887c725976bd604234b
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5-website/+/35475
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: Bobby R. Bruce <bbruce@ucdavis.edu>
7 files changed