Create table for storing requirements test results

This is a first step towards connecting CI results with requirements. Let's suppose there is a manual job in CI with meaning "I confirmed that requirements are met" (#215510 (closed)). The plan is that when user manually triggers this job, then this job will automatically fill record(s) which requirements were met and confirmed by the user.

We need a model and table (or multiple tables) which would store which requirements were confirmed by who and when. So each record should keep following info:

• pipeline_id - pipeline from which the manual "confirmation" job was triggered
• user_id - user who triggered the job (confirmed requirements)
• timestamp - when the requirement was confirmed
• requirement_id - requirement which was confirmed - for the first iteration these would be all open requirements (at the time when the job was triggered- so we should create this record for each requirement)
• state - for the first iteration all states will be set automatically to passed, in a next iteration when we connect tests with requirements, the state might be different

The name for this model/table is not settled yet, a few times before terms like "test session" or "test report" were used, but this is still something to clarify, also UX designs might help choosing proper name for this.

Update: Test report is the preferred term (see #215506 (comment 331185212)).

Related to &2859 (closed)