tickvals and ticktext don't work with subcategory axes

If a plot has multi-category axes there is no way to hide a subcategory labels only and the plot doesn't render at all if tickvals and ticktext are used.

Look at the code without multi-categories:

x_names = ['very.long.name.1', 'very.long.name.2', 'very.long.name.3']
fig = go.Figure(go.Bar(
    x=x_names,
    y=[10, 20, 30]))
fig.update_layout(
    xaxis=dict(
        tickvals=x_names,
        ticktext=['', '', ''],
    ))

This works fine and all x-axes labels are hidden. I could achieve the same thing with this:
fig.update_layout(xaxis=dict(showticklabels=False))

However, if this is a multi-category plot it doesn't work at all:

x_names = [['A', 'A', 'B'], ['very.long.name.1', 'very.long.name.2', 'very.long.name.3']]
fig = go.Figure(go.Bar(
    x=x_names,
    y=[10, 20, 30]))
fig.update_layout(
    xaxis=dict(
        tickvals=x_names,
        ticktext=[['A', 'A', 'B'], ['', '', '']],
    ))

Setting showticklabels=False hides everything and I didn't find a way to hide just a single category labels.

What is really surprising this doesn't work either even if this doesn't change anything:

x_names = [['A', 'A', 'B'], ['very.long.name.1', 'very.long.name.2', 'very.long.name.3']]
fig = go.Figure(go.Bar(
    x=x_names,
    y=[10, 20, 30]))
fig.update_layout(
    xaxis=dict(
        tickvals=x_names,
        ticktext=x_names,
    ))

I believe it should work like this:

• tickvals and ticktext work fine with a multi-category plots
• showticklabels should accept a list of booleans, .e.g. [True, False] to be able to hide a given subcategory if this is a multi-category plot

Beginne damit, die Beispiele für Einzelkategorien und mehrere Kategorien im Issue zu reproduzieren und das resultierende Achsenverhalten zu vergleichen. Verfolge, wie Achsen mit mehreren Kategorien xaxis.tickvals, ticktext und showticklabels verarbeiten; abgeschlossen ist dies, wenn tickvals und ticktext für Plots mit mehreren Kategorien funktionieren und einzelne Kategorienbeschriftungen ausgeblendet werden können.