fix: Context::execute_sync_items: Ignore all errors (#4817)

An error while executing an item mustn't prevent next items from being executed. There was a comment
that only critical errors like db write failures must be reported upstack, but in fact it's hard to
achieve in the current design, there are no error codes or so, so it's bug-prone. E.g.
`ChatAction::Block` and `Unblock` already reported all errors upstack. So, let's make error handling
the same as everywhere and just ignore any errors in the item execution loop. In the worst case we
just do more unsuccessful db writes f.e.

src/chat.rs

@@ -4274,9 +4274,6 @@ impl Context {
             }
             ChatAction::SetContacts(addrs) => set_contacts_by_addrs(self, chat_id, addrs).await,
         }
-        .log_err(self)
-        .ok();
-        Ok(())
     }
 }