Release v0.15.3

Release notes

• Added #1294 Ability to bulk delete using client and site
• Fixed #1250 Race condition causing windows agent update to sometimes fail
• Fixed #25 Cleanup agent update temp files
• Fixed slow dashboard loading when lots of pending actions in db
• Various dependency updates

New Contributors

• @Can-eh-dian11 made their first contribution in #1294

Full Changelog: v0.15.2...v0.15.3