fix: memory leak on conversation

Conversation view controllers was not destroyed after reopening

Change-Id: I5137f84e4d3de13b221e4ad1c2a4f86360fab64b
Reviewed-by: Andreas Traczyk <andreas.traczyk@savoirfairelinux.com>
diff --git a/Ring/Ring/Features/Conversations/Conversation/ConversationViewController.swift b/Ring/Ring/Features/Conversations/Conversation/ConversationViewController.swift
index c19d70b..48d6ed8 100644
--- a/Ring/Ring/Features/Conversations/Conversation/ConversationViewController.swift
+++ b/Ring/Ring/Features/Conversations/Conversation/ConversationViewController.swift
@@ -533,16 +533,16 @@
             self.viewModel.sendMessage(withContent: "👍")
         }).disposed(by: self.disposeBag)
 
-        self.messageAccessoryView.messageTextViewHeight.asObservable().subscribe(onNext: { height in
+        self.messageAccessoryView.messageTextViewHeight.asObservable().subscribe(onNext: { [unowned self] height in
             self.tableView.contentInset.bottom = self.bottomHeight + height - 35
             self.tableView.scrollIndicatorInsets.bottom = self.bottomHeight + height - 35
             self.scrollToBottom(animated: true)
             self.updateBottomOffset()
-        })
+        }).disposed(by: self.disposeBag)
 
-        self.messageAccessoryView.messageTextViewContent.asObservable().subscribe(onNext: { height in
+        self.messageAccessoryView.messageTextViewContent.asObservable().subscribe(onNext: { [unowned self] _ in
             self.messageAccessoryView.editingChanges()
-        })
+        }).disposed(by: self.disposeBag)
     }
 
     // Avoid the keyboard to be hidden when the Send button is touched