[ci] install uv into venv, have uv handle the rest

maybe this will work

.woodpecker/workflow.yaml

@@ -26,6 +26,6 @@ steps:
     commands:
       - python -m venv venv
       - . venv/bin/activate
-      - python -m pip install --no-deps --quiet -r requirements.txt -r requirements.dev.txt
-      - uv run pytest tests.py
+      - pip install --disable-pip-version-check --require-virtualenv --quiet uv==0.9.16
+      - uv run --active pytest tests.py
       # coverage: uv run pytest tests.py --cov-report= --cov=src # no cov report on terminal: useful for CI