v0.28.4

Changelog

5ac224d disable snapcraft
892ff60 Update release.yml
a3fbd9b Merge pull request #75 from peteole/master
6ff14e3 Fixed list-installed error
36ca7bd Merge pull request #74 from SaaldjorMike/mike/custom_useragent
2fc3ed0 Allow custom 'User-Agent' header
ce92f7b Merge pull request #73 from humio/mike/only_set_auth_header_if_nonempty
3451374 Only set Authorization header if non-empty.