Formatter's `is_decorated` property is temporarily disabled during `remove_format` breaking concurrent threads

[vfazio]

See https://github.com/python-poetry/poetry/issues/9334

Poetry relies on the formatter's is_decorated property to be consistent when multiple threads query the property.

If one thread is in the middle of updating a section and has changed the formatter's is_decorated property via remove_format, a second thread may query it and get back an incorrect result.

If cleo is not thread-safe, the developers of poetry should be made aware, otherwise there may need to be changes to how remove_format and format work in relation to whether decorated output is supported in general vs decorated output is being emitted for the current format operation.