D3 5.16.0: data.labels.format regression

[florentmontesano]

Found a regression in data.labels.format:
The j parameter used to be the sub index of the data point but is now an array of SVGTextElement. Might be a regression due to the new d3.js version.
Below the CodePen showing the issue.

Before (D3 3.5.16): https://codepen.io/florentmontesano/pen/PoxoBYG
After (D3 5.16.0): https://codepen.io/florentmontesano/pen/jOQOKjG

• C3 version: 0.7.20
• D3 version: 5.16.0
• Browser: Chrome 114.0.5735.110
• OS: Windows 10