tns test init --help doesn't show the available unit testing frameworks

[Fatme]

tns test init --help doesn't show the available unit testing frameworks as the constant constants.TESTING_FRAMEWORKS that is used from the test-init.md file was deleted. On the other side, test-dependencies.json file was introduced in order to list all supported frameworks. So, this PR gets the supported unit testing framework names from test-dependencies.json file and prints them from test-init.md file.

Rel to: #5113

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What is the current behavior?

What is the new behavior?

Fixes/Implements/Closes #[Issue Number].