There is no longer any reason for these to be intertwined.
This deliberately avoids touching some files as much as possible because
they are super tangled and due to be replaced. Those files are:
* fdroidserver/build.py
* fdroidserver/update.py
# Conflicts:
# tests/testcommon.py
# Conflicts:
# fdroidserver/btlog.py
# fdroidserver/import_subcommand.py
The existing logic from d1ddd525c in !1225 is confusing because it adds its
own retry loop on top of the retry mechanism that is built into requests.
So this test confirms that setting `download_file(retries=3)` actually
results in more than three retries.
