[1.10.x] Fixed #26677 -- Converted some i18n tests to use disposable FS tree.

This allows makemessages/compilemessages tests in `test_extraction.py`
and `test_compilation.py` to actually run isolated from each other
(unaffected by stray FS objects left by cleanup actions failures, debug
sessions, etc.) and to take advantage of the parallel tests execution
feature like most of the Django test suite.

`test_percents.py` gets slightly refactored to not inherit from the new
machinery which sets up every test case to copy and run under a
temporary tree.

Backport of faeeb84edfebecf5a5f40df9ef816e5f1cd457c6 from master

0 files changed, 0 insertions, 0 deletions