Convert src/categories/delete.js to typescript

[wacker22]

• Converted src/categories/delete.js to typescript
• Adjusted test cases that conflicted with typescript conversion close #22

[coveralls]

Pull Request Test Coverage Report for Build 7745434153

• -6 of 50 (88.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.001%) to 85.094%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/categories/delete.js	44	50	88.0%
<!--	Total:	44	50	88.0%	-->

Totals
Change from base Build 7649102120:	0.001%
Covered Lines:	22633
Relevant Lines:	25363

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💛 - Coveralls