Description

Allow null value through tristate property for CheckboxListTile (exactly like Checkbox).
The docstring has been copied from the Checkbox class

Related Issues

#58108

Tests

I added the following tests:

• Setting new tristate property to true and tap few times to change value. Exactly likeCheckbox tristate test

Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
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• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
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• I updated/added relevant documentation (doc comments with ///).
• All existing and new tests are passing.
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Breaking Change

Did any tests fail when you ran them? Please read Handling breaking changes.

• No, no existing tests failed, so this is not a breaking change.
• Yes, this is a breaking change. If not, delete the remainder of this section.
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