Pipeline stages meta

[sagar1312]

Context

Objective

Render below meta info for a stage in the UI

• Job count in the header next to stage name
• Border color based on individual job/build statuses within a stage

Examples: https://github.com/sagar1312/screwdriver-config/blob/main/stage-with-failure/screwdriver.yaml

References

https://github.com/screwdriver-cd/screwdriver/issues/2669

License

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