Try enabling cache for pip dependencies

Author: gudnimg

.github/workflows/ci.yml

@@ -95,6 +95,8 @@ jobs:
             3.13
             pypy3.11
           allow-prereleases: true
+          cache: "pip"
+          cache-dependency-path: pyproject.toml
       - name: Enable UTF-8 on Windows
         run: echo "PYTHONUTF8=1" >> $env:GITHUB_ENV
         if: runner.os == 'Windows' && startsWith(matrix.noxenv, 'tests')