calculate token lease TTL using tune config

[ccapurso]

Description

The max_lease_ttl config of the token backend is not used to constrain a token's TTL when creating a token directly using the auth/token/create endpoint. Instead, the system level default is used.

This PR introduces a fix that calculates a token's TTL by using the tuned max_lease_ttl value.

ENT PR: https://github.com/hashicorp/vault-enterprise/pull/6706

TODO only if you're a HashiCorp employee

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  • If this fixes a critical security vulnerability or severity 1 bug, it will also need to be backported to the current LTS versions of Vault. To ensure this, use all available enterprise labels.
• ENT Breakage: If this PR either 1) removes a public function OR 2) changes the signature
  of a public function, even if that change is in a CE file, double check that
  applying the patch for this PR to the ENT repo and running tests doesn't
  break any tests. Sometimes ENT only tests rely on public functions in CE
  files.
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  description. Also, make sure the changelog is in this PR, not in your ENT PR.

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