[UX] Redirect in app trial iteration: Add a message to highlight new security features after users started a trial from the security dashboard

Experiment hypothesis

Proposed solution

Add a message to highlight new security features after users started a trial from the security dashboard.

Flow

📐 Specs

How do we measure success?

We'll measure the impact of the changes on Security features adoption after starting a trial (Secure usage rate) while monitoring conversion rate.

• Current secure usage rate: TBC on results from #300871 (closed)
• Targeted secure usage rate: TBC on results from #300871 (closed)