wide-mode type checking too strict

[nicolaskruchten]

As reported in https://community.plotly.com/t/df-plot-kind-box-with-plotly-returns-error-of-wide-form-data/40729/5?u=nicolaskruchten it would be nice if a mix of floats and ints were still accepted for wide-mode processing, rather than strictly saying the types don't match.