Add "Trending posts" (statuses) feed (#4007)

Add "Trending posts" (statuses) feed.

This feed is a good source of interesting accounts to follow and,
personally, a sort of "Front page of the Fediverse".

Since #3908 and #3910 (which would provide a more thorough, albeit
complex, access to trending things) won't get merged, I'd like to
address this missing feed by simply adding another tab/feed.

~~If desired, I can move the second commit (fixing lint) to another
PR.~~

## Screenshots
### Tab
<img
src="https://github.com/tuskyapp/Tusky/assets/1063155/6a71a97e-673e-44c7-b67d-9b1df0bed4f5"
width=320 /> <img
src="https://github.com/tuskyapp/Tusky/assets/1063155/9bf60b23-d2f3-4dd8-8af6-e96647b02121"
width=320 />

### Activity
<img
src="https://github.com/tuskyapp/Tusky/assets/1063155/4e07dea3-d97f-42c6-8551-492a3116fcfa"
width=320 /> <img
src="https://github.com/tuskyapp/Tusky/assets/1063155/ad00a134-d622-43f4-8305-84cfa7fed706"
width=320 />

app/src/main/java/com/keylesspalace/tusky/TabPreferenceActivity.kt

@@ -386,6 +386,10 @@ class TabPreferenceActivity : BaseActivity(), Injectable, ItemInteractionListene
         if (!currentTabs.contains(trendingTagsTab)) {
             addableTabs.add(bookmarksTab)
         }
+        val trendingStatusesTab = createTabDataFromId(TRENDING_STATUSES)
+        if (!currentTabs.contains(trendingStatusesTab)) {
+            addableTabs.add(trendingStatusesTab)
+        }
 
         addableTabs.add(createTabDataFromId(HASHTAG))
         addableTabs.add(createTabDataFromId(LIST))