Fix Issue with Lost Timezone in Metadata for Database Secret Engines

[ltcarbonell]

Description

This PR fixes an issue where the Location object in the metadata is lost when converting entries to JSON for storage in all database secret engines. As a result, the "local" timezone was missing upon retrieval, causing it to default to UTC. This fix ensures that the Location object retains its value, so the correct timezone is preserved when reading from storage.

TODO only if you're a HashiCorp employee

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  to N, N-1, and N-2, using the backport/ent/x.x.x+ent labels. If this PR is in the CE repo, you should only backport to N, using the backport/x.x.x label, not the enterprise labels.
  • 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
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CI Results:
All Go tests succeeded! ✅

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Build Results:
All builds succeeded! ✅

[fairclothjm]

Thank you!

[fairclothjm]

@ltcarbonell I think we will want to backport this