ci: remove deprecated workflow for creating release. This would prevent accidental trigger of this workflow

[Darien-Lin]

Description
Currently, the release is controlled in another defined workflow. Spoke with @ericzzzzzzz and he confirmed that this workflow is no longer used and should be deleted.

[code-review-assist]

Hi team,

I'm currently reviewing this pull request and will post my full review in a few minutes. In the meantime, here's a quick summary to help you and other reviewers get up to speed:

This pull request removes the deprecated draft-release.yml workflow from the Skaffold repository. The workflow was previously used for creating releases but has been superseded by a different workflow. The removal prevents accidental triggering of this outdated workflow, improving the CI/CD process and reducing potential confusion.

Specifically, the entire .github/workflows/draft-release.yml file has been deleted. This file contained a GitHub Actions workflow responsible for creating draft releases. The change is straightforward and addresses a clear need for cleanup and maintenance of the CI/CD pipeline.

Happy reviewing!

A tiny poem for your coding pleasure:

Old workflows sleep,
New systems rise, clean and bright,
Progress takes flight.

[code-review-assist]

This pull request removes the deprecated draft-release.yml workflow. This is a good cleanup and prevents accidental triggers. The PR description clearly explains the reason for the change and references the discussion with @ericzzzzzzz, which is helpful for context. Since the entire file is being removed, there aren't specific line-by-line code suggestions to offer. However, I recommend updating any documentation or READMEs that might reference this workflow to reflect its removal. Additionally, ensure there are alternative mechanisms in place for creating releases, and that those are well-documented.