SMTP setup: tell user about test email

[noahtalerman]

Goal

User story
As an admin configuring SMTP,
I want to see a message explaining that saving changes sends a test email
so that I can check my inbox to make sure SMTP is properly configured.

Key result

Original requests

• SMTP setup: clarify that a test email is sent #25109

Context

• Product designer: @rachaelshaw

Changes

Product

• UI changes: Figma
• CLI (fleetctl) usage changes: No changes
• YAML changes: No changes
• REST API changes: No changes
• Fleet's agent (fleetd) changes: No changes
• Activity changes: No changes
• Permissions changes: No changes
• Changes to paid features or tiers: No changes
• Transparency changes: No changes
• First draft of test plan added
• Other reference documentation changes: No changes
• Once shipped, requester has been notified
• Once shipped, dogfooding issue has been filed

Engineering

• Test plan is finalized @xpkoala
• Feature guide changes: no need
• Database schema migrations: no need
• Load testing: no need

ℹ️  Please read this issue carefully and understand it. Pay special attention to UI wireframes, especially "dev notes".

QA

Risk assessment

• Requires load testing: no need
• Risk level: Low
• Risk description: very low. tooltip change.

Test plan

1. Go to /settings/organization/smtp and hover over Save button.
   • Should see tooltip explaining that a test email will be sent.
2. Enable GitOps mode and go to /settings/organization/smtp and hover over disabled Save button.
   • Should see GitOps mode tooltip instead of test email tooltip.
3. Go to /settings/organization/smtp with FLEET_EMAIL_BACKEND=ses
   • Message displayed instead of the form should now have a border around it.
   • Resize the screen to smallest supported screen size and make sure there are no style issues.

Testing notes

Confirmation

1. Engineer: Added comment to user story confirming successful completion of test plan.
2. QA: Added comment to user story confirming successful completion of test plan.

[noahtalerman]

Hey @sharon-fdm just a reminder that this user story and another user story here are ready to spec.

Can you please complete the "TO-DOs" in the Engineering section so we can estimate these today?