promtail: Give access to the logrotated nginx access.log files

The files are initially created by nginx as 0644/http:root, but when logrotate rotates the files it creates the new files as 0640/http:log, which promtail can't read.

Fix the issue by adding the log group as a supplementary group.

approved this merge request

added 7 commits

• aa523a32...d99f2fc0 - 6 commits from branch archlinux:master
• 754686de - promtail: Give access to the logrotated nginx access.log files

Compare with previous version

mentioned in commit 24c85844

merged