Fix crash when creating menu actions for status w/o URL

Tusker/Screens/Utilities/Previewing.swift

@@ -176,13 +176,18 @@ extension MenuActionProvider {
         guard let accountID = mastodonController.accountInfo?.id,
               let account = mastodonController.account else {
             // user is logged out
+            // i don't know why exactly a status wouldn't have a url, but apparently it happens, so:
+            if let url = status.url {
                 return [
-                openInSafariAction(url: status.url!),
+                    openInSafariAction(url: url),
                     createAction(identifier: "share", title: "Share", systemImageName: "square.and.arrow.up", handler: { [weak self] (_) in
                         guard let self = self else { return }
                         self.navigationDelegate?.showMoreOptions(forStatus: status.id, source: source)
-                })
+                    }),
                 ]
+            } else {
+                return []
+            }
         }
         let bookmarked = status.bookmarked ?? false