Run the lint job under Python 3.10

.github/workflows/build.yml

@@ -23,7 +23,21 @@ jobs:
       - id: setup-python
         uses: actions/setup-python@v4
         with:
-          python-version: "3.11"
+          # Temporarily hold back support for Python 3.11 due to the
+          # version pin for the PyMuPDF package. Pre-built wheels for
+          # Python 3.11 were not made available until the 1.21.0
+          # release and building the PyMuPDF package from source
+          # proves problematic due to dependencies. Please see the
+          # following issue for more information:
+          # https://github.com/cisagov/pe-reports/issues/441
+          #
+          # It's also the case that we cannot build the wheel for
+          # reportlab under Python 3.11 because its C code accesses
+          # the C struct members of PyFrameObject directly, and these
+          # struct members are no longer public as of Python 3.11.
+          # See here for more details:
+          # https://docs.python.org/3/whatsnew/3.11.html#pyframeobject-3-11-hiding
+          python-version: "3.10"
       # We need the Go version and Go cache location for the actions/cache step,
       # so the Go installation must happen before that.
       - id: setup-go