Feature: Maximum height for posts behind content warning

[sk22]

The post in the screenshot is way larger, I think the problem is obvious. There really should be a maximum height (that ideally doesn't cut off very long content warnings either) for posts behind content warnings.

[sk22]

Fixed this in my fork, but not creating a pull request here for now because https://github.com/mastodon/mastodon-android/issues/22#issuecomment-1304762602

[waldyrious]

IMO a nicer solution could be adjusting the placement of the spoiler tag text so that it's always on-screen, without changing the height of the spoiler area. Quoting myself from #419:

Ideally the text should have a "sticky" positioning, so that it can still be in the vertical center of the post when that doesn't place it off-screen, but would otherwise remain visible (stuck to the top or the bottom of the visible area).