Instead of testing the legacy `SourcesServer` and `sources.get`,
test the `Source.download` method, which is the new and exclusive
way how sources are used in osbuild. For this, the complete info
for a specific source is now included the specific test case.
For the `org.osbuild.curl` source this means that the respective
information is moved from `sources.json`, which is then unused
and thus removed. The test case that checks for an unknown
checksum is also removed because `Source.download` just fetches
everything instead of a subset.
The `org.osbuild.files` source provides files, but might in the
future not be the only one that does. Therefore rename it to
match the internal tool that is being used to fetch the files.
This is done for most other osbuild modules that target tools.
The format v1 loader is adapted to make this change transparent
for users of the v1 format, so we are backwards compatible.
Change the MPP depsolve preprocessor so that for format v2 based
manifest `org.osbuild.curl` source is used. Also rename the
corresponding source test. Adapt the format v2 mod test to use
the curl source.
This moves the `sources_tests` into ./test/data/sources/ and makes the
entire test use `locate_test_data()` to get relative paths for their
accesses.
This further improves our test cases to support running from
installments rather than local checkouts. We need access to ./test/data
guarded, so we can install packages and still have the tests access the
correct paths.
This also adjusts the HTTP-Server we use in the test to serve data
relative to a path it is handed. I now chose `./test/data`, which will
easily allow us to re-use the same HTTP-Server in the future for other
tests that require it.
