This simplifies the hover component by eagerly converting all
`lsp::Hover` responses into `Markdown`s. Previously we cached the
current `Markdown` and created a new `Markdown` when switching the
active response. Instead we can consume the `lsp::Hover` and avoid some
clones of its inner types.
The Hover component is used as the inner contents of a Popup. The Popup
should be doing calculations based on whether popup_borders is
configured and not Hover. This fixes an issue with hover rendering when
the popup border option is enabled for popups.
Fixes#12742
Michael Davis
kyfanc