R1:d9e034f02ca0

Remove calls to getCallsign() from repository daemons

Summary: Ref T4245. These are all descriptive or UI-facing.

Test Plan:
- Ran `bin/repository pull ...` with various identifiers.
- Ran `bin/repository mirror ...` with various identifiers.
- Ran `bin/repository discover ...` with various identifiers.
- Ran `bin/phd debug pull X Y --not Z` with various identifiers.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T4245

Differential Revision: https://secure.phabricator.com/D14926