Cache public key

[dholth]

Checklist

• I added a descriptive title
• I searched open requests and couldn't find a duplicate

What is the idea?

Don't create new PublicKey() for each signature verification, when many are being verified against the same key. May save ~750ms.

Why is this needed?

Discovered from benchmark https://github.com/conda/conda-content-trust/actions/runs/6163081698/job/16725868947#step:8:133

What should happen?

conda-content-trust (or the calling code in conda) should create one PublicKey() per unique signing key.

Additional Context

No response

[mohanavamsi20]

use one key for every unique signing key, it makes it faster and more efficient than creating new for each signature

[github-actions]

Hi there, thank you for your contribution!

This issue has been automatically marked as stale because it has not had recent activity. It will be closed automatically if no further activity occurs.

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Thanks!