How to create a key that never expires

[OneSeven]

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Steps for Reproduction

1. Set up the following "xxxx" value in the config.yaml configuration file
2. Launch binary with the following arguments
3. Step Two
4. Step Three

Expected behavior:
Create a key that does not expire
Actual behavior:
The TTL type only supports time.Duration and cannot pass in negative values
Platforms:

Include browser, operating system and respective versions

Versions:
3.1.1
Which versions are you running?