Fix admin certificate regeneration/usage in data node system index reindex

[moesterheld]

Description

The admin certificate was used after its expiry because the refresh of the transport was not triggered correctly.
This PR fixes this and swaps the transport with a new one with a fresh certificate on demand if the certificate would be expired.

Motivation and Context

/nocl fixes error introduced during development

How Has This Been Tested?

reduced lifetime of certificate, made two calls to AdminIndicesAdapter so the second call would have used an expired certificate, made sure that a new one was minted

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring (non-breaking change)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have requested a documentation update.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.

[todvora]

LGTM, thanks for the fix!