Add test for other categories.

[usmangurowa]

Some test are already available for major categories like link, email, post, code, json etc (you can check the text-categorizer.test.ts file to see the available test).

However, some categories are missing a test.

[usmangurowa]

@onoja123 you think you can handle this?

[onoja123]

@onoja123 you think you can handle this?

@usmangurowa will take a look at it and revert.