tests/test-gendoc-sv.t

pycompat: remove large Python 2 block

We no longer support Python 2. So we can delete its compatibility
code and remove the conditional and dedent the Python 3 code.

In order to make the linter happy, we had to inline imports in the
stanza at the top of the file.

Differential Revision: https://phab.mercurial-scm.org/D12250

#require docutils gettext

  $ $TESTDIR/check-gendoc sv
  checking for parse errors