Revert "Use pytest.mark to selectively skip test."
Revert "Use pytest.mark to selectively skip test."

Markers can not be applied to fixtures (https://docs.pytest.org/en/latest/reference/reference.html#marks). Fixes #16.

This reverts commit 14d532af265e35af33a28d61a68d545993fc5b78.

jaraco/tempora