[Entity Analytics] Audit clean-up of data in Cypress

[MadameSheema]

Relates to:

#173327
#174247

Each spec file is executed on a clean environment, but, retries are not. Retries are executed on the same environment the execution was initiated, this is why is pretty important to make sure that the data the test may generate is cleaned at the beginning.

We need to make sure that the data the test might generate during its execution is properly cleaned. The best way to clean data is to make sure that all the data the test might generate or create is deleted at the beginning of it in a beforeEach hook.

Making this exercise is beneficial as well to end-up having tests that are independent of each other.

[elasticmachine]

Pinging @elastic/security-entity-analytics (Team:Entity Analytics)

[elasticmachine]

Pinging @elastic/security-solution (Team: SecuritySolution)