Fix bug in assertions returning true for some tests

[galadim1]

Previous issues
Most of the existing tests were written incorrectly.
The assertions are inside a promise which does not return. The test will always return true.

Improvements Done

1. All tests which does not return anything were rewritten
2. Await/async used instead of done/done() for deprecation error tests

How to properly test
To properly test;

1. Clone the repo
2. Change any assertion
3. Run the test
4. The test should fail e.g

For more context, here is the shortcut ticket
https://app.shortcut.com/chartmogul/story/57880/rewrite-the-assertion-in-chartmogul-node-library

[shortcut-integration]

This pull request has been linked to Shortcut Story #57880: Rewrite the assertion in Chartmogul Node library.

[kamilpavlicko]

LGTM, great refactoring

[whobubble]

Test suite works (Tested locally)
package.json formatting can be reverted