vault: default tlsSkipVerify to false

[mismithhisler]

Description

The transit keyring uses the go-kms-wrapper for parsing the vault config and errors if tlsSkipVerify is an empty string. We should ensure TLSSkipVerify is defaulting to false.

Testing & Reproduction steps

Links

Fixes GH #26596

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Changes to Security Controls

Are there any changes to security controls (access controls, encryption, logging) in this pull request? If so, explain.