ci: Workaround bug preventing Django test runs

Workaround pypa/setuptools#4519 by constraining `setuptools<72.0.0` when installing dependencies for Django tests.

Author: szokeasaurusrex

.github/workflows/test-integrations-web-frameworks-1.yml

@@ -64,6 +64,7 @@ jobs:
       - name: Test django latest
         run: |
           set -x # print commands that are executed
+          export PIP_CONSTRAINT=constraints.txt
           ./scripts/runtox.sh "py${{ matrix.python-version }}-django-latest"
       - name: Test flask latest
         run: |
@@ -140,6 +141,7 @@ jobs:
       - name: Test django pinned
         run: |
           set -x # print commands that are executed
+          export PIP_CONSTRAINT=constraints.txt
           ./scripts/runtox.sh --exclude-latest "py${{ matrix.python-version }}-django"
       - name: Test flask pinned
         run: |

constraints.txt

@@ -0,0 +1,3 @@
+# Workaround for https://github.com/pypa/setuptools/issues/4519.
+# Applies only for Django tests.
+setuptools<72.0.0