fix: backport PR need individual assignees

[github-actions]

This is the main issue tracking #88

Please add labels indicating the release versions eg. 'release/v0'

Please add comments for user issues which this issue addresses.

Description copied from PR:

Related Issue

Addresses #5

Description

Assigns backport PRs to individuals rather than the team, I think maybe even PRs can't be assigned to a team only the reviewers can be a team.

Testing

actionlint

Not a breaking change.

[matttrach]

ready for release