Run integration test CI in parallel (#8156)

.github/workflows/integration.yaml

@@ -27,6 +27,11 @@ jobs:
     name: Integration Tests
     runs-on: ubuntu-20.04
     timeout-minutes: 45
+    strategy:
+      fail-fast: false
+      matrix:
+        itest: [certrotation, etcdrestore, localstorage, startup, custometcdargs, etcdsnapshot, kubeflags, longhorn, secretsencryption]
+      max-parallel: 3
     steps:
     - name: Checkout
       uses: actions/checkout@v3
@@ -49,7 +54,7 @@ jobs:
     - name: Run Integration Tests
       run: | 
         chmod +x ./dist/artifacts/k3s
-        sudo -E env "PATH=$PATH" go test -v ./tests/integration/... -run Integration
+        sudo -E env "PATH=$PATH" go test -v -timeout=45m ./tests/integration/${{ matrix.itest }}/... -run Integration
     - name: On Failure, Launch Debug Session
       if: ${{ failure() }}
       uses: mxschmitt/action-tmate@v3