Make it even more super obvious when there's a distro update error

This commit makes it *even more* super obvious what you should do when
you encounter an update issue, in the following ways:

- *Explicitly* tell people to report it to their distro, and mention the
  distro by name
- Also put the name of the distro on the "report a bug" button
- Make the "report a bug" button physically larger and the "copy text"
  button physically smaller by changing their labels, so that the
  "report a bug" button has more visual prominence
- Separate the two buttons with whitespace so they don't blend into one
  another
- When the "copy text" button is clicked, show a message repeating the
  instructions to report the issue to the distro, not to KDE