Update deprecations and removals

Author: BurntimeX

docs/migration/wsc62/deprecations_removals.md

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+# Migrating from WoltLab Suite 6.2 - Deprecations and Removals
+
+With version 6.3, we have deprecated certain components and removed several other components that have been deprecated for many years.
+
+## Deprecations
+
+### PHP
+
+#### Classes
+
+
+#### Methods
+
+
+#### Variables
+
+
+### JavaScript
+
+
+
+## Removals
+
+### PHP
+
+#### Classes
+
+- `gallery\page\AlbumListFeedPage`
+- `gallery\page\UnreadAlbumListPage`
+- `gallery\system\page\handler\UnreadAlbumListPageHandler`
+- `gallery\data\album\ViewableAlbum`
+- `gallery\data\album\ViewableAlbumList`
+- `gallery\data\album\FeedAlbum`
+- `gallery\data\album\FeedAlbumList`
+
+#### Methods
+
+- `gallery\data\album\Album::setCoverImage()`
+- `gallery\data\album\Album::setCoverImages()`
+- `gallery\data\album\Album::setUserProfile()`
+
+#### Properties
+
+
+### JavaScript
+