feat: add authors for issue entries

[kzantow]

This adds PR authors for issue entries.

The current Grype changelog looks like this:

# Changelog

## [(Unreleased)](https://github.com/anchore/grype/tree/) (2023-01-23)

[Full Changelog](https://github.com/anchore/grype/compare/v0.55.0...)

### Added Features

- Allow db diff to specify local files [[Issue #1059](https://github.com/anchore/grype/issues/1059)] [[kzantow](https://github.com/kzantow)]

### Bug Fixes

- False positive CVE-2015-5237 for protobuf-go [[Issue #558](https://github.com/anchore/grype/issues/558)] [[luhring](https://github.com/luhring)]
- Getting many warnings (empty ID, unable to read golang buildinfo, bin parsing) when running grype from command line and directing stderr to file [[Issue #1050](https://github.com/anchore/grype/issues/1050)]
- Missing severities in embedded-cyclonedx-vex-json format since v0.55.0 [[Issue #1066](https://github.com/anchore/grype/issues/1066)] [[kzantow](https://github.com/kzantow)]

[kzantow]

Just sneaking in a fix -- this was reading a url from the vulnerability-match-labels or other remote because it was multiline and had a .* in the middle.

[wagoodman]

great catch