A bug in Packit that caused purging or syncing upstream changelog
(when not configured) from specfile when running propose-downstream was fixed.
New behavior preserves downstream changelog and in case there are either
no entries or no %changelog section present, it is created with a new entry.
packit source-git init was updated to try to apply patches with git am first, and use patch only when this fails, in order to keep the commit message of Git-formatted (mbox) patch files in the source-git history. (packit#1358)