Make tox.ini uv-ready

tox.ini

@@ -29,18 +29,18 @@ commands =
 [testenv:py3{7,10,12}-tests]
 extras = cov
 # Python 3.6+ has a number of compile-time warnings on invalid string escapes.
-# PYTHONWARNINGS=d and --no-compile below make them visible during the tox run.
+# PYTHONWARNINGS=d makes them visible during the tox run.
 set_env =
  COVERAGE_PROCESS_START={toxinidir}/pyproject.toml
  PYTHONWARNINGS=d
-install_command = python -Im pip install --no-compile {opts} {packages}
 commands_pre = python -c 'import pathlib; pathlib.Path("{env_site_packages_dir}/cov.pth").write_text("import coverage; coverage.process_startup()")'
 commands = coverage run -m pytest {posargs:-n auto}
 
 
 [testenv:coverage-report]
 # Keep base_python in-sync with .python-version-default
 base_python = py312
+# Keep depends in-sync with testenv above that has cov extra.
 depends = py3{7,10,12}
 skip_install = true
 deps = coverage[toml]>=5.3