This image will now automatically reconfigure `daemon_directory` in case
of distrubution switching.
Alpine and Debian/Ubuntu will use different directly layout and if the
user persists `/etc/postfix`, this image will not start if the
distribution changes.
This will change the `deamon_directory` if it detects a distribution
change. Some distributions will by default set the `deamon_directory` in
`main.cf` and they differentiate between distributions. Hence, updating
to another distribution causes Postfix to fail starting.
Building fails with a really bad exception:
```
=> ERROR [linux/386 builder 5/8] RUN go mod download 0.5s
------
> [linux/386 builder 5/8] RUN go mod download:
```
There's some weird bug where building the exporter for `linux/mips64le`
and `linux/arm/v5` has go complaining how
(go-systemd)[https://github.com/coreos/go-systemd/tree/main] has no
linux packages.
We're taking a quick-and-ditry route here and hope that nobody's going
to use the postfix-exporter on MIPS / ARMv5, which hopefully won't be such a big
issue.
We now include logrotate in the the basic image. This does -- up to a
point -- reduce the "separation of concerns", but it simplifies image
management considerably and removes an unneccessary dependency on a
third-party container.
To not repeat outselves, building of postfix-exporter was moved to a
separate action.
Helm now always references the lastest version, as there's no sense in
having specific versions which are all the same.
Lastly, the build fails in the test phase, as it relies on an external
dependency and hence tests have been (temporarily, at least) removed
from the build cycle. This should prove to be a large issue, as we're
building from a fixed SHA hash which we know to be valid.
As noted in https://helm.sh/docs/topics/charts/#the-chartyaml-file, a helm chart's version must be semver 2.0.0.
Since semver 2.0.0 strictly prescribes the "{major}.{minor}.{patch}" format, the shell string interpolation is used to remove the `v` prefix
