added worflow for backend formatting

.github/workflows/backend-format.yml

@@ -0,0 +1,26 @@
+name: Backend Black Format
+
+on:
+  push:
+    paths:
+      - '*.py'
+  pull_request:
+    paths:
+      - '*.py'
+
+jobs:
+  format:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out source repository
+        uses: actions/checkout@v3
+
+      - name: Set up Python environment
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.10"
+
+      - name: Black Format
+        run: |
+          pip3 install -r requirements.txt
+          black --config=./backend/pyproject.toml --preview ./backend