chore(tox): Fix UV environment variables for pre-release tests

Author: effigies

tox.ini

@@ -59,7 +59,8 @@ deps =
 extras = tests
 setenv =
   pre: PIP_EXTRA_INDEX_URL=https://pypi.anaconda.org/scientific-python-nightly-wheels/simple
-  pre: UV_EXTRA_INDEX_URL=https://pypi.anaconda.org/scientific-python-nightly-wheels/simple
+  pre: UV_INDEX=https://pypi.anaconda.org/scientific-python-nightly-wheels/simple
+  pre: UV_INDEX_STRATEGY=unsafe-best-match
 uv_resolution =
   min: lowest-direct