Feature/pla 162 make vespa search adapter code in the sdk not require certs

[THOR300]

Description

This PR provides:

• A method of opting out of trying to find vespa certs.

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[linear]

PLA-162 Make Vespa Search Adapter code in the SDK not require certs

[jesse-c]

Approving to un-block, though I wonder if instead of this inreasingly more complex logic, an option is added for someone to explicitly say to skip certificate usage?

[katybaulch]

lgtm 🦖