Handle text_set where text are only wrapped in ''

[exetico]

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#355 (comment)

As a end-user, I expect this to work:

        - service: floorplan.text_set
          service_data: 'Multiline\nTSPAN-Print2'

With new the end-user needs to do this:

        - service: floorplan.text_set
          service_data: '${"Multiline\nTSPAN-Print2"}'

I'm unsure if it's related to how YAML handles the \n if ' ... ' are used. So its unsure if it's possible to fix, without a ugly work-around. I'd need to check that, before concluding anything.