forms-flow-web: Create small GitHub Action CI/CD pipeline

[acoard-aot]

Describe the task
Create a small GitHub Action pipeline for deploying forms-flow-web to openshift. Should mirror existing CI/CD pipeline as much as possible in interface, but steps to deploy will have to differ as the build process is different.

Likely:

dev -> OCP dev
main -> OCP test
prod -> can we hook into release script? Otherwise, manual for now until we polish off those scripts.

Acceptance Criteria

• Deployment GitHub Actions are setup for dev and main

Additional context

• Mostly a CD task - any CI or tests to run?