viewproperties: remove temp file after loading defaultConfig
It turns out that since MR (!905 (merged)) a temp file is created here with each save() call for this default config, which is not deleted later. In another place where defaultProperties() is called for m_node, the file is deleted in the destructor of this class. But it is not deleted here.
So, remove temp file after loading defaultConfig or it will create temp file on each save() operation in /tmp folder.
I know that this MR (!1118 (merged)) is designed to solve the problem of creating temporary files in general. But I thought maybe this fix would be useful for some kind of temporary solution until !1118 (merged) is released.