Add Python support to Tekton Pipelines

This post details the addition of Python support to Tekton Pipelines, building upon existing Java and JavaScript pipeline work. It outlines the architecture of Tekton Pipelines (Tasks, Steps, Pipelines, PipelineRuns) and describes the three main tasks involved in creating a Python CI/CD pipeline: 1. Installing a virtual environment and necessary app dependencies using pip. 2. Packaging the app source code and filtered virtual environment into a zip file. 3. Modifying the OpenWhisk runtime Dockerfile to include the zipped code as an environment variable and building the image using Kaniko Executor. It also provides an example PipelineRun and Knative service deployment.