fix(type): add undefined to the return type of graphic.clipRectByRect function

[benlongo]

Brief Information

This pull request is in the type of:

• bug fixing
• new feature
• others

What does this PR do?

Add | undefined to return type of graphic.clipRectByRect.

Fixed issues

Details

Before: What was the problem?

graphic.clipRectByRect can return undefined, but this is not reflected in it's type signature.

After: How does it behave after the fixing?

graphic.clipRectByRect has undefined as a possible return type.

Document Info

One of the following should be checked.

• This PR doesn't relate to document changes
• The document should be updated later
• The document changes have been made in apache/echarts-doc#xxx

Misc

ZRender Changes

• This PR depends on ZRender changes (ecomfe/zrender#xxx).

Related test cases or examples to use the new APIs

N.A.

Others

Merging options

• Please squash the commits into a single one when merging.

Other information

[echarts-bot]

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[echarts-bot]

Congratulations! Your PR has been merged. Thanks for your contribution! 👍