[Breaking Change] Change TaskRunResult.Value and PipelineRunResult.Value from string to ArrayOrString

[Yongxuanzhang]

This PR(#4818) and following PR(will update this issue once opened) will change TaskRunResult.Value and PipelineRunResult.Value from string to ArrayOrString and this will be breaking changes for cli as pointed out by @pritidesai.

Background:
This is a requested feature in TEP0076

Please be aware of this change. 🙏

/cc @tektoncd/cli-maintainers

[abayer]

Is this done? Can this be closed?

[Yongxuanzhang]

Is this done? Can this be closed?

yeah, this is done.