ci: enable mgr suite for PR only

this commit enable mgr suite to run only
for PRs.

Signed-off-by: subhamkrai <srai@redhat.com>

.github/workflows/integration-test-mgr-suite.yaml

@@ -3,7 +3,6 @@ on: [pull_request]
 
 jobs:
   TestCephMgrSuite:
-    if: ${{ github.event_name == 'pull_request' && github.ref != 'refs/heads/master' }}
     runs-on: ubuntu-18.04
     strategy:
       fail-fast: false
@@ -65,62 +64,3 @@ jobs:
     - name: setup tmate session for debugging
       if: failure() && contains(github.event.pull_request.labels.*.name, 'debug-mgr-suite')
       uses: mxschmitt/action-tmate@v3
-
-  TestCephMgrSuite-Master:
-    if: github.ref == 'refs/heads/master' || github.ref == 'refs/tags/release-*'
-    runs-on: ubuntu-18.04
-    strategy:
-      fail-fast: false
-      matrix:
-        kubernetes-versions : ['v1.15.12','v1.16.15','v1.18.15','v1.19.7','v1.20.2']
-    steps:
-    - name: checkout
-      uses: actions/checkout@v2
-
-    - name: setup golang
-      uses: actions/setup-go@v2
-      with:
-        go-version: 1.15
-
-    - name: setup minikube
-      uses: manusa/actions-setup-minikube@v2.3.1
-      with:
-        minikube version: 'v1.16.0'
-        kubernetes version: ${{ matrix.kubernetes-versions }}
-        start args: --memory 6g --cpus=2
-
-    - name: check k8s cluster status
-      run: |
-        kubectl cluster-info
-        kubectl get pods -n kube-system
-
-    - name: use local disk
-      run: |
-        sudo swapoff --all --verbose
-        sudo umount /mnt
-        # search for the device since it keeps changing between sda and sdb
-        sudo wipefs --all --force /dev/$(lsblk|awk '/14G/ {print $1}'| head -1)1
-        sudo lsblk
-
-    - name: build rook
-      run: |
-        # set VERSION to a dummy value since Jenkins normally sets it for us. Do this to make Helm happy and not fail with "Error: Invalid Semantic Version"
-        GOPATH=$(go env GOPATH) make clean && make -j$nproc IMAGES='ceph' VERSION=0 build
-        docker images
-        docker tag $(docker images|awk '/build-/ {print $1}') rook/ceph:master
-
-    - name: TestCephMgrSuite
-      run: |
-       export DEVICE_FILTER=$(lsblk|awk '/14G/ {print $1}'| head -1)
-       go test -v -timeout 1800s -run CephMgrSuite github.com/rook/rook/tests/integration
-
-    - name: Artifact
-      uses: actions/upload-artifact@v2
-      if: failure()
-      with:
-        name: ceph-mgr-suite-artifact
-        path: /home/runner/work/rook/rook/tests/integration/_output/tests/
-
-    - name: setup tmate session for debugging
-      if: failure() && contains(github.event.pull_request.labels.*.name, 'debug-mgr-suite')
-      uses: mxschmitt/action-tmate@v3