Journey linger charts in orange/red don't show orange/red on main page

Even if a chart on the server node -specific page is in orange/red, that doesn't also show on the main page as such.

We have:

```
echo "journey_top90linger.warning 0:600"
echo "journey_top90linger.critical 0:700"
```

so I'm not really sure what is wrong.

There's a StackExchange question which is so far unanswered on this same topic:
https://unix.stackexchange.com/questions/635513/