Remove the redis-tls, wfe-tls, and mail-test-srv keys which were
generated by minica and then checked in to the repo. All three are
replaced by the dynamically-generated ipki directory.
Part of https://github.com/letsencrypt/boulder/issues/7476
Integrate the key-value rate limits from #6947 into the WFE. Rate limits
are backed by the Redis source added in #7016, and use the SRV record
shard discovery added in #7042.
Part of #5545