Update balena etcher references to point to 1.18.11 closes PhotonVision/photonvision-docs#357

[samfreund]

Update links to balena etcher to point to 1.18.11 and change the warning against older versions to only warn against versions older than 1.18.11, as it is not the newest version.

[mcm001]

Lgtm 🛥️

[samfreund]

PR is finalized

[mcm001]

Two raspberry pi links are broken -- could you update those rq? The pi docs should be updated to point to either https://github.com/raspberrypi/documentation/blob/679fab721855a3e8f17aa51819e5c2a7c447e98d/documentation/asciidoc/computers/camera/rpicam_configuration.adoc#L15 or https://github.com/raspberrypi/documentation/blob/679fab721855a3e8f17aa51819e5c2a7c447e98d/documentation/asciidoc/computers/camera/rpicam_apps_intro.adoc I think?

[samfreund]

I replaced this link with this one

I couldn't find the second broken link, so if you could point that one out, that would be great.

[samfreund]

I found the second one, it looks like it's this link. It is not passing the check, but the link is functional, both from the build of the documentation and by copying and pasting into a browser. I'm not quite sure why it's failing the check.

As it's giving a 403, I'm assuming that something specific to the check means it can't access it, perhaps the raspberry pi site has some sort of captcha. I don't believe this affects anything, however, and I think we should be good to go.