Fix #nsfw tag filtering to be case insensitive

Closes: https://github.com/damus-io/damus/issues/3131

Changelog-Fixed: Fixed #nsfw tag filtering to be case insensitive
Signed-off-by: Terry Yiu <git@tyiu.xyz>

damus/Models/ContentFilters.swift

@@ -31,7 +31,7 @@ enum FilterState : Int {
 
 /// Simple filter to determine whether to show posts with #nsfw tags
 func nsfw_tag_filter(ev: NostrEvent) -> Bool {
-    return ev.referenced_hashtags.first(where: { t in t.hashtag == "nsfw" }) == nil
+    return ev.referenced_hashtags.first(where: { t in t.hashtag.caseInsensitiveCompare("nsfw") == .orderedSame }) == nil
 }
 
 func get_repost_of_muted_user_filter(damus_state: DamusState) -> ((_ ev: NostrEvent) -> Bool) {