Rename default SSH key name from Phabricator to Phorge

Summary:
Rename default SSH key name from Phabricator to Phorge

Closes T15274

Test Plan: Go to https://we.phorge.it/settings/panel/ssh/ and select SSH Key Actions > Generate Keypair

Reviewers: O1 Blessed Committers, avivey, valerio.bozzolan

Reviewed By: O1 Blessed Committers, avivey, valerio.bozzolan

Subscribers: avivey, speck, tobiaswiese, valerio.bozzolan, Matthew, Cigaryno

Maniphest Tasks: T15274

Differential Revision: https://we.phorge.it/D25135