Describe the feature or problem you’d like to solve

When we create a release using Web UI, we can specify the previous tag for generating release notes.

This feature enables us to list pull requests we publish.

But, gh release create command do not support it.

Proposed solution

I propose to add the --previous-tag flag to specify the previous tag.

For example, sample repository have two tags: v1.1.0 and v1.1.1

# Use automatically generated release notes without previous tag.
# Create a diff between v1.2.0 and v1.1.1.
$ gh release create v1.2.0 --generate-notes

# Use automatically generated release notes with previous tag.
# Create a diff between v1.2.0 and v1.1.0.
$ gh release create v1.2.0 --generate-notes --previous-tag v1.1.0

Additional context

GitHub Web UI