Adding colorbars with "inherit_position=False" does not work as expected

[raphaelquast]

Describe the bug

Using m.add_colorbar(inherit_position=False) only works if a colorbar already exists on the associated layer.

To Reproduce

m = Maps()
m.set_data([1,2,3], [1,2,3], [1,2,3])
m.plot_map()
m2.add_colorbar()

m2 = m.new_layer("my_layer", inherit_data=True)
m2.plot_map()
m2.add_colorbar(inherit_position=False)   # this does NOT create an independent colorbar!

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Possible workaround:

m2.add_colorbar(inherit_position=False).remove()
m2.add_colorbar(inherit_position=False)