[TTL] ttl duration should not allow 0

[cangfengzhs]

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Describe the bug (required)

(root@nebula) [nba]> CREATE EDGE ttl_edge02(a timestamp, b int) ttl_duration=0, ttl_col="a";
Execution succeeded (time spent 1246/1598 us)

Your Environments (required)

• OS: uname -a
• Compiler: g++ --version or clang++ --version
• CPU: lscpu
• Commit id (e.g. a3ffc7d8)

How To Reproduce(required)

Steps to reproduce the behavior:

1. Step 1
2. Step 2
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Expected behavior

Additional context