add addition label to release label workflow

[derrickaw]

1. Existing release label workflow considers 5 different labels with one being improvement. To me improvement would be about improving on existing code to make it faster, better logic, etc.
2. There is another label addition that seems to be geared more to new features and such, so adding that label to the release label check.
3. Also, making the labels in alphanumeric order.
4. If reviewer thinks we should not do this, should we just delete the addition label to minimize confusion with the release label workflow? Thanks.

[gemini-code-assist]

Note

Gemini is unable to generate a summary for this pull request due to the file types involved not being currently supported.

[Abacn]

This SGTM. "addition" is currently used by Issue. Yeah we can use it to label PRs as well.

cc: @damccorm @aasthabharill @rahulkumar0630
(developers contributed recently) FYI the label addition, and in case you have inputs

[damccorm]

Thanks!