fix to not remove call buttons for federated conversations after 30 seconds

After 30 seconds (when the capabilities were updated) the call buttons of federated conversations were removed (this was done back then when fed calls were not implemented).

However this happened not always because of the check
"if (this::spreedCapabilities.isInitialized) {...."
It seems this check sometimes is false when it's supposed to be true. This has be to further investigated and has to be be simplified/improved by a cleaner architecture.

Signed-off-by: Marcel Hibbe <dev@mhibbe.de>

app/src/main/java/com/nextcloud/talk/chat/ChatActivity.kt

@@ -2812,10 +2812,7 @@ class ChatActivity :
                 menu.removeItem(R.id.shared_items)
             }
 
-            if (currentConversation!!.remoteServer != null) {
-                menu.removeItem(R.id.conversation_video_call)
-                menu.removeItem(R.id.conversation_voice_call)
-            } else if (CapabilitiesUtil.isAbleToCall(spreedCapabilities)) {
+            if (CapabilitiesUtil.isAbleToCall(spreedCapabilities)) {
                 conversationVoiceCallMenuItem = menu.findItem(R.id.conversation_voice_call)
                 conversationVideoMenuItem = menu.findItem(R.id.conversation_video_call)