fix: hush "replaying transcripts" message during swingset startup

This removes one of the two noisy log messages from kernel startup. This
mostly gets noticed in tests like test-message-patterns.js which launches
dozens of swingsets in a single test. We included it because sometimes errors
occur (and get logged to the console) during transcript replay, and it wasn't
obvious when/why the vat was being invoked so early. But to be properly
useful for that, we'd need to announce the replay phase of each vat
separately, as well as the *end* of replay for each vat, multiplying the
noise by at least an order of magnitude.

Instead, just remove the message, and if/when someone needs to figure this
out, go ahead and temporarily add it back. Besides, transcript replay is
going to change drastically with the introduction of the
vat-manager-manger (#2277), which would have removed the place where this
message was emitted anyways.

packages/SwingSet/src/kernel/kernel.js

@@ -842,7 +842,6 @@ export default function buildKernel(
     // replay any transcripts
     // This happens every time, now that initialisation is separated from
     // execution.
-    console.log('Replaying SwingSet transcripts');
     const oldLength = kernelKeeper.getRunQueueLength();
     for (const vatID of ephemeral.vats.keys()) {
       logStartup(`Replaying transcript of vatID ${vatID}`);