[SES-337] Add rounded corners to thumbnail in QuoteView

[bemusementpark]

Corner Radius was not set on one codepath to setting images in ThumbnailView

Utilised in some other classes, but hopefully an improvement if any change at all. If there's any unintentional rounding, we just need to set radius to 0.

MediaGalleryAdapter.java
AlbumThumbnailView.kt
LinkPreviewDraftView.kt
LinkPreviewView.kt