benchmark workflow added

.github/workflows/benchmark.yml

@@ -0,0 +1,36 @@
+name: Benchmark
+
+on:
+  pull_request:
+    types: [ labeled ]
+
+jobs:
+  Run_benchmarks:
+    if: ${{ github.event.label.name == 'benchmark' }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Benchmark Repo
+        uses: actions/checkout@v3
+        with:
+          repository: django/django-asv
+          path: "."
+      - name: Install Requirements
+        run: pip install -r requirements.txt
+      - name: Cache Django
+        uses: actions/cache@v3
+        with:
+          path: Django/*
+          key: Django
+      - name: Run Benchmarks
+        shell: bash -l {0}
+        run: |-
+          asv machine --machine ubuntu-latest --yes
+          echo '```' >> $GITHUB_STEP_SUMMARY
+          asv continuous --interleave-processes -a processes=2 --split --show-stderr 'HEAD^' 'HEAD' |\
+          sed -n -E '/(before.*after.*ratio)|(BENCHMARKS)/,$p' >> out.txt
+          cat out.txt >> $GITHUB_STEP_SUMMARY
+          echo '```' >> $GITHUB_STEP_SUMMARY
+          if grep -q "PERFORMANCE DECREASED" out.txt;
+          then
+            exit 1
+          fi