Revert "Revert "Update 'salt' details for EncryptHeader AuthToken details (#6881)" (#6902)"

[sfc-gh-ahusain]

Description

Major changes proposed:

1. This reverts commit f38b2e8.
2. Also add fix for Valgrind failure due to unintialized variables.
3. Improve checks to catch is cipherKey details cached in BlobCipherKeyCache
   isn't as expected

Testing

Overall correctness: 10K (20220421-193911-ahusain-foundationdb-a730e5cb38541e20)
EncyrptionOps correctness: 100K (20220421-194315-ahusain-foundationdb-29c598a8b9420430)
EncryptionOps Valgrind: 100 (20220421-194434-ahusain-foundationdb-7fc5f98eddc0921a)

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[fdb-windows-ci]

Doxense CI Report for Windows 10

• Commit ID: 658bd01
• Result: ✔️ SUCCEEDED
• Build Logs (available for 30 days)

[foundationdb-ci]

AWS CodeBuild CI Report for Linux CentOS 7

• CodeBuild project: foundationdb-pr
• Commit ID: 658bd01
• Result: FAILED
• Error: Build has timed out.
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[foundationdb-ci]

AWS CodeBuild CI Report for Linux CentOS 7

• CodeBuild project: foundationdb-pr
• Commit ID: 658bd01
• Result: SUCCEEDED
• Error: N/A
• Build Logs (available for 30 days)