Migrating tekton pipeline integration from prow to tekton

This PR allows us to run the tektonCD/pipeline's integration tests on the tekton dogfooding cluster using a pipeline instead of a prow job.

Before merging, the tekton dogfooding cluster needs to be updated as follows:
1. Set up a node pool similar to prow cluster’s “n2-standard-4-kind” node pool.
    - ie. Add same Taints, auto scaling 0-24, us-central1 etc.
2. create a secret for test-account (same as prow) to store the service-account.json credentials

tekton/ci/jobs/kustomization.yaml

@@ -13,3 +13,4 @@ resources:
 - tekton-yamllint.yaml
 - tekton-github-tasks-completed.yaml
 - tekton-golang-coverage.yaml
+- tekton-integration-tests.yaml

tekton/ci/repos/pipeline/template.yaml

@@ -103,3 +103,117 @@
           value: post-tekton-pipeline-go-coverage
         - name: uploadGcsBucket
           value: tekton-prow
+  - apiVersion: tekton.dev/v1beta1
+    kind: PipelineRun
+    metadata:
+      generateName: run-integration-tests-
+      labels:
+        prow.k8s.io/build-id: $(tt.params.buildUUID)
+        tekton.dev/source-event-id: $(tt.params.sourceEventId)
+        tekton.dev/check-name: pull-tekton-pipeline-integration-tests-using-tekton
+        tekton.dev/kind: ci
+        tekton.dev/pr-number: $(tt.params.pullRequestNumber)
+      annotations:
+        tekton.dev/gitRevision: "$(tt.params.gitRevision)"
+        tekton.dev/gitURL: "$(tt.params.gitRepository)"
+    spec:
+      pipelineRef:
+        name: integration-test-pipeline
+      workspaces:
+        - name: source
+          volumeClaimTemplate:
+            spec:
+              accessModes:
+                - ReadWriteOnce
+              resources:
+                requests:
+                  storage: 1Gi
+        - name: test-account
+          secret:
+            secretName: test-account
+      params:
+        - name: jobName
+          value: pull-tekton-pipeline-integration-tests-using-tekton
+        - name: gitHubCommand
+          value: $(tt.params.gitHubCommand)
+        - name: package
+          value: $(tt.params.package)
+        - name: pullRequestNumber
+          value: $(tt.params.pullRequestNumber)
+        - name: pullRequestBaseRef
+          value: $(tt.params.pullRequestBaseRef)
+        - name: e2eClusterRegion
+          value: "us-central1"
+        - name: k8sVersion
+          value: "v1.23.x"
+        - name: nodes
+          value: "3"
+        - name: e2eScript
+          value: "./test/e2e-tests.sh"
+        - name: e2eEnv
+          value: "./test/e2e-tests-kind-prow.env"
+      podTemplate:
+        nodeSelector:
+          cloud.google.com/gke-nodepool: "n2-standard-4-kind"
+        tolerations:
+          - key: kind-only
+            operator: Equal
+            value: "true"
+            effect: NoSchedule
+  - apiVersion: tekton.dev/v1beta1
+    kind: PipelineRun
+    metadata:
+      generateName: run-alpha-integration-tests-
+      labels:
+        prow.k8s.io/build-id: $(tt.params.buildUUID)
+        tekton.dev/source-event-id: $(tt.params.sourceEventId)
+        tekton.dev/check-name: pull-tekton-pipeline-alpha-integration-tests-using-tekton
+        tekton.dev/kind: ci
+        tekton.dev/pr-number: $(tt.params.pullRequestNumber)
+      annotations:
+        tekton.dev/gitRevision: "$(tt.params.gitRevision)"
+        tekton.dev/gitURL: "$(tt.params.gitRepository)"
+    spec:
+      pipelineRef:
+        name: integration-test-pipeline
+      workspaces:
+        - name: source
+          volumeClaimTemplate:
+            spec:
+              accessModes:
+                - ReadWriteOnce
+              resources:
+                requests:
+                  storage: 1Gi
+        - name: test-account
+          secret:
+            secretName: test-account
+      params:
+        - name: jobName
+          value: pull-tekton-pipeline-alpha-integration-tests-using-tekton
+        - name: gitHubCommand
+          value: $(tt.params.gitHubCommand)
+        - name: package
+          value: $(tt.params.package)
+        - name: pullRequestNumber
+          value: $(tt.params.pullRequestNumber)
+        - name: pullRequestBaseRef
+          value: $(tt.params.pullRequestBaseRef)
+        - name: e2eClusterRegion
+          value: "us-central1"
+        - name: k8sVersion
+          value: "v1.23.x"
+        - name: nodes
+          value: "3"
+        - name: e2eScript
+          value: "./test/e2e-tests.sh"
+        - name: e2eEnv
+          value: "./test/e2e-tests-kind-prow-alpha.env"
+      podTemplate:
+        nodeSelector:
+          cloud.google.com/gke-nodepool: "n2-standard-4-kind"
+        tolerations:
+          - key: kind-only
+            operator: Equal
+            value: "true"
+            effect: NoSchedule