Background issues on GitHub Enterprise

[chimericdream]

On GHE, the diff backgrounds do not extend through the code. This makes it difficult to see where the diff lines are. The cause is an extra <pre> tag that needs to be styled. PR coming shortly.

[Mottie]

Hi @chimericdream!

We would greatly appreciate it if you would check and/or update the style for the new Enterprise Instance Health page! Pretty please with cat nip on top! 😻

If the colors of the graph are off (hopefully it's all svg), then you can copy or merge it into the styling we already have for the graph page.

Thanks!