Fix default no-op reverse migrations
Fix default no-op reverse migrations

By default the reverse migration path was set to `os.path.join(self.base_path, reverse_template) -> "some/base/path/SELECT 1"`, which is clearly wrong, but that was passed over because `RunSqlLazy._render_template` erroneously always used `self.sql` (which confusingly is initialized with the forward migration template path) as the template path rather than the argument provided.
dimagi/commcare-hq,dimagi/commcare-hq,dimagi/commcare-hq,dimagi/commcare-hq,dimagi/commcare-hq