Hex decode add-prefix and remove-prefix for fdbrestore.

[newhook]

This is fix for #1537.

--add-prefix and --remove-prefix command line arguments to fdbrestore are not hex decoded.

This also fixes a bug in the original decode_hex_string implementation where an error condition is not correctly flagged.

I tested the implementation locally and it works as expected.

Once this PR is merged I can create a fix against main.

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[jzhou77]

Maybe refactor this into a separate file to be shared with FileDecoder.actor.cpp.

[newhook]

I did that. Added Decode.cpp.

[foundationdb-ci]

Result of foundationdb-pr-macos-m1 on macOS Ventura 13.x

• Commit ID: 5d3e226
• Duration 0:32:44
• 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-macos on macOS Ventura 13.x

• Commit ID: 5d3e226
• Duration 0:44:58
• 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: 5d3e226
• Duration 0:47:04
• 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: 5d3e226
• Duration 0:53:04
• 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)

[foundationdb-ci]

Result of foundationdb-pr on Linux CentOS 7

• Commit ID: 5d3e226
• Duration 1:03:08
• 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: 146161a
• Duration 0:53:57
• 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)

[foundationdb-ci]

Result of foundationdb-pr-clang on Linux CentOS 7

• Commit ID: 146161a
• Duration 1:15:34
• 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 on Linux CentOS 7

• Commit ID: 146161a
• Duration 1:16:05
• 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)