Use a different cluster for pr e2e runs (#2283)

Signed-off-by: Ahmed ElSayed <ahmed@elsayed.io>

.github/workflows/pr-e2e.yml

@@ -39,7 +39,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Execute e2e tests
     container: ghcr.io/kedacore/build-tools:main
-    concurrency: e2e-tests
+    concurrency: pr-e2e-tests
     if: needs.check.outputs.run-e2e == '1'
     steps:
       - uses: actions/checkout@v2
@@ -88,6 +88,7 @@ jobs:
           AZURE_DEVOPS_POOL_NAME: ${{ secrets.AZURE_DEVOPS_POOL_NAME }}
           AZURE_DEVOPS_PROJECT: ${{ secrets.AZURE_DEVOPS_PROJECT }}
           E2E_IMAGE_TAG: "pr-${{ steps.checkout.outputs.pr_num }}"
+          TEST_CLUSTER_NAME: keda-pr-run
         run: |
           MESSAGE="${{ github.event.comment.body }}"
           REGEX='/run-e2e (.+)'