commitsigs & Mercurial 5.6

[A. Klitzing]

Hi there,

the latest Mercurial 5.6 changed "files" on the changeset object and
broke the extension commitsigs.
As I don't have enough experience about that new "API" it would be
nice if someone could help here.
How can I get the same files from new API as provided from the old API
to avoid breaking existing hashes?

https://foss.heptapod.net/mercurial/commitsigs/-/blob/branch/default/commitsigs.py#L216

Best regards
   André Klitzing