Fix KeyRangeRef::isCovered() (#9675)

[sfc-gh-huliu]

This PR fixed a bug in KeyRangeRef:isCovered(), which is used by hybrid restore.

cherry pick #9675

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[fdb-windows-ci]

Doxense CI Report for Windows 10

• Commit ID: d8ca0f6
• Result: ✔️ SUCCEEDED
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[foundationdb-ci]

Result of foundationdb-pr on Linux CentOS 7

• Commit ID: d8ca0f6
• Duration 0:59:46
• Result: ✅ SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr-clang on Linux CentOS 7

• Commit ID: d8ca0f6
• Duration 1:02:42
• Result: ✅ SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr-cluster-tests on Linux CentOS 7

• Commit ID: d8ca0f6
• Duration 1:24:50
• Result: ✅ SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)
• Cluster Test Logs zip file of the test logs (available for 30 days)

[sfc-gh-akejriwal]

Please add the main PR number in the description so that Github can link the two PRs.

[sfc-gh-huliu]

Please add the main PR number in the description so that Github can link the two PRs.

Done. thank you!