* Pass unknown props through to the div element
This fits common React conventions and allows using attributes such as `data-testid` for testing purposes.
Related changes:
- Adding HTMLAttributes<HTMLDivElement> to EChartsReactProps meant that EChartsReactProps was no longer usable as a `Record<string, unknown>`, which caused problems for the `pick` function. (See https://stackoverflow.com/q/65799316/25507.). I updated the pick function to use a generic type instead.
- Add [ignoreRestSiblings](https://eslint.org/docs/latest/rules/no-unused-vars#ignorerestsiblings) so ESLint is happy with the new code.
- Fix an unrelated Prettier warning in `componentDidUpdate`.
There's a slight risk of backwards-incompatible changes in this release: IF the user previously passed unknown props (e.g., due to typos or mistaken props spreads), they were ignored, but they're now passed through to the div element.
Fixes#546
* Update tests
* Code review
