fix: pass digest to publicKeyFromProtobuf

[achingbrain]

This with the changes from #3013 roughly doubles the throughput of loading RSA peers from the peer store which is a massive bottleneck when restarting the amino bootstrapper.

Before:

 % node benchmarks/load-peers.js
read all x 5.94 ops/sec ±1.37% (33 runs sampled)

After:

% node benchmarks/load-peers.js
read all x 12.43 ops/sec ±1.18% (63 runs sampled)

Change checklist

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation if necessary (this includes comments as well)
• I have added tests that prove my fix is effective or that my feature works

[achingbrain]

Needs #3013