Result/version.err is out of sync with release

[rjsparks]

Having the output of version captured in source-control this way is strange - premise of test needs to be reconsidered.

If we keep this file in source-control, the version of svgcheck itself needs to be updated as part of release.

It would probably be better to compute the desired result at test runtime, given that we have rfctools_common>=0.6.0 in requirements.txt. An update of that package would cause the tests of this one to start failing...

We should also move to using constraints.txt and use that and svgcheck.init.py as the source for the computation for the expected output.