Switch from pip to uv, during tox (#324)

Significantly speeds up CI. Does not require contributors to use uv directly, outside of tox.

Author: john-kurkowski

.github/workflows/ci.yml

@@ -41,7 +41,7 @@ jobs:
           check-latest: true
       - name: Install Python requirements
         run: |
-          pip install --upgrade tox
+          pip install --upgrade tox tox-uv
       - name: Test
         run: tox
         env:

pyproject.toml

@@ -55,6 +55,7 @@ testing = [
     "ruff",
     "syrupy",
     "tox",
+    "tox-uv",
     "types-filelock",
     "types-requests",
 ]