(GitHub automation): Auto-lock-script should also auto-unlock

[rix0rrr]

Describe the bug

Came up in #33335

When a PR or issue is reopened, a human has to remember to also unlock the discussion.

We should automate that, such that always the state closed == locked.

Regression Issue

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Last Known Working CDK Library Version

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Expected Behavior

Current Behavior

Reproduction Steps

Possible Solution

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Additional Information/Context

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AWS CDK Library version (aws-cdk-lib)

AWS CDK CLI version

Node.js Version

OS

Language

TypeScript

Language Version

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Other information

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