Error: <path> attribute d: Expected moveto path command ('M' or 'm'), "null".

Hi there,

I am trying to create a line chart with both negative and positive values and highlight the chart based on the value (exactly like here: https://nivo.rocks/storybook/?path=/story/line--highlighting-negative-values) It’s all good and it works perfectly fine but there is an annoying case: when i end up having no negative values, I get this error in console: Error: <path> attribute d: Expected moveto path command ('M' or 'm'), "null"

To Reproduce I’ve created two sandboxes:

• one with the error: https://codesandbox.io/s/nivo-highlight-negative-colors-with-no-negative-values-wypw3?file=/src/index.js
• and one that works when having both negative and positive values: https://codesandbox.io/s/nivo-highlight-negative-values-638nz?file=/src/index.js

The sandbox uses nivo@0.71.0 but it’s also reproducible in v0.74.0.

Screenshots

As I can see, this doesn’t influence the behaviour of the chart, it just throws that annoying error in the console.

Thank you for this awesome library! 🙏🙏