refactor(tekton/v1,tekton/v1): add GitHub TriggerBindings and reorganize triggers (#3905)
Add TriggerBinding manifests for branch create/push, PR, tag create, and issue comment. Reorganize trigger files into env-gcp and add an env-prod2 kustomization. Migrate PingCAP-QE artifact trigger to tekton v1 and update TaskRun apiVersion. (commit: 1368d61)