enos(replication): wait for both clusters to be healthy before enabling replication

[ryancragun]

Description

Fix a race where we might configure replication before getting secondary cluster IP addresses when using shamir seals.

TODO only if you're a HashiCorp employee

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[ryancragun]

I verified this locally with 8x replication scenarios using shamir seals and didn't see the race behavior.

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Build Results:
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CI Results:
All Go tests succeeded! ✅