Martin von Zweigbergk <martinvonz@google.com> [Mon, 19 Apr 2021 10:49:15 -0700] rev 46975
errors: make OutOfBandError extend Abort
I'm about to create a new `RemoteError` exception and make
`OutOfBandError` extend it. This patch prepares for that.
Differential Revision: https://phab.mercurial-scm.org/D10465