Search microdescriptor files for relay ed25519 keys

Your code in legacy/trac#33428 (moved) needs to pass your local "make test-network-all", before you start this ticket.

We need to enable searching for ed25519 keys in relay microdescriptor files.

There are instructions and a draft search pattern here: https://github.com/torproject/chutney/blob/master/lib/chutney/TorNet.py#L1325

Please open a new pull request for this ticket. Your branch should be based on the final version of legacy/trac#33428 (moved).

Before you push new changes to your pull request, your chutney code should pass:

• "make test-network-all" on tor master
• "make test-network-all" on tor maint-0.3.5

You can build a tor branch using these commands:

cd tor
git checkout -b <branch>
make

Where is master or maint-0.3.5