Add working ci for flask test suite. (pallets#3177)

Author: Rowlando13

.github/workflows/test-flask.yaml

@@ -0,0 +1,25 @@
+name: Test Flask Main
+on:
+  pull_request:
+    paths-ignore: ['docs/**', 'README.md']
+  push:
+    branches: [main, stable]
+    paths-ignore: ['docs/**', 'README.md']
+jobs:
+  flask-tests:
+    name: flask-tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: astral-sh/setup-uv@5a7eac68fb9809dea845d802897dc5c723910fa3 # v7.1.3
+        with:
+          enable-cache: true
+          prune-cache: false
+      - run: git clone https://github.com/pallets/flask
+      - run: uv venv --python 3.14
+        working-directory: ./flask
+      - run: source .venv/bin/activate
+        working-directory: ./flask
+      - run: uv sync --all-extras
+        working-directory: ./flask
+      - run: uv run --with "git+https://github.com/pallets/click.git@main" -- pytest
+        working-directory: ./flask