Add Fanout payload to SNS messages

[waisingyiu]

What's changed?

Implementation notes

Checklist

General

• 🤖 Relevant tests added
• ✅ CI checks / tests run locally
• 🔍 Checked on CODE

Client

• 🚫 No obvious console errors on the client (i.e. React dev mode errors)
• 🎛️ No regressions with existing user interactions (i.e. all existing buttons, inputs etc. work)
• 📷 Screenshots / GIFs of relevant UI changes included

[github-actions]

Deploy build 8463 of cms-fronts::facia-tool to CODE

All deployment options

• Deploy build 8463 of cms-fronts::facia-tool to CODE
• Deploy parts of build 8463 to CODE by previewing it first
• What's on CODE right now?

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From guardian/actions-riff-raff.

[github-actions]

This PR is stale because it has been open 30 days with no activity. Unless a comment is added or the “stale” label removed, this will be closed in 3 days