Define decimal places for chart

[jwillmer]

Checklist

• [x ] I am running the latest version of the card
• [x ] I checked if there isn't another feature request opened with the same request
• [x ] I checked that the feature is not already available in the dev branch

Describe the solution you'd like
I can define decimal places on the scale but they are not respected in displaying the values or for the steps. For energy prices it is vital to see two decimal places:

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This issue was closed because it has been stalled for 10 days with no activity.