TextEditor: Do not overwrite existing indenters

In 6959618d7b a default indenter was set
on all text editor factories.
Unfortunately some editors, like the C++ editor, set their indenter in
the text document constructor, which would then be overridden by this
default indenter.
For now remove the default indenter again until this is better thought
through.

Partially reverts 6959618d7b.

Change-Id: I8f32e92438883edb6be853fa838b75297347a937
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/texteditor/texteditor.cpp

@@ -8542,7 +8542,6 @@ public:
     TextEditorFactoryPrivate(TextEditorFactory *parent)
         : q(parent)
         , m_widgetCreator([]() { return new TextEditorWidget; })
-        , m_indenterCreator([](QTextDocument *d) { return new TextIndenter(d); })
     {}
 
     BaseTextEditor *duplicateTextEditor(BaseTextEditor *other)