test(accordion): add missing tests

[ParsaArvanehPA]

Before submitting a pull request, please make sure you have at least performed the following:

• [x] read and followed the CONTRIBUTING.md and DEVELOPER.md guide.
• [x] built and tested the changes locally.
• [x] added/updated any applicable tests.
• [x] added/updated any applicable API documentation.
• [x] added/updated any applicable demos.

🔶 Notes:

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Branches	100%	100%
Functions	97.61%	100%
Lines	99.17%	100%