Print SRE FQDN when deployment finishes

[craddm]

✅ Checklist

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🚦 Depends on

⤴️ Summary

Exports the sre_fqdn to the SRE stack, prints the FQDN at the end of the deployment process.

🌂 Related issues

Closes #2274

🔬 Tests

Tested locally

[github-actions]

Coverage report

Click to see where and how coverage changed

File	Statements	Missing	Coverage	Coverage (new stmts)	Lines missing
data_safe_haven/commands
sre.py					167
data_safe_haven/infrastructure/programs
declarative_sre.py					423
Project Total

This report was generated by python-coverage-comment-action

[JimMadge]

Looks good, could we have an example of the output?

[JimMadge]