SETTINGS.layout gets mutated during plotting

[ssfrr]

It seems that sometimes the process of merging together a plot layout and the global layout is mutating the global layout.

To reproduce:

PlotlyLight.reset!()
Preset.PlotContainer.settings!(
    layout=Config(xaxis=Config(automargin=true)))
expected_layout = Config(xaxis=Config(automargin=true))
PlotlyLight.SETTINGS.layout == expected_layout # true
Plot(x=rand(10),y=rand(10),layout=Config(
    xaxis=Config(
        title=Config(
            text="myX"))))
PlotlyLight.SETTINGS.layout == expected_layout # no longer true

At the end, the SETTINGS.layout has acquired the xaxis.title.text field

[joshday]

Thanks for the report! It's a silly bug in EasyConfig that will be fixed ASAP.