Merge branch 'develop' into 'master'

Refinements

See merge request !2

.hadolint.yaml

 ignored:
-  - DL3008

README.md

 # nut-upsd
 
+[![pipeline status](https://git.ethitter.com/docker/nut-upsd/badges/master/pipeline.svg)](https://git.ethitter.com/docker/nut-upsd/commits/master)
+
 Fully-customizable `nut` instance in a container. Many images exist, but they are
 feature-limited due to how `nut`'s configuration is handled. This image aims to
 provide all `nut` options without making too many compromises.

context/Dockerfile

@@ -7,7 +7,7 @@ RUN echo "deb http://security.debian.org/ buster/updates main" >> /etc/apt/sourc
 
 RUN apt-get update \
     && apt-get -y --no-install-recommends install \
-        nut \
+        nut=2.7.4-8 \
     && apt-get autoremove -y \
     && apt-get clean \
     && rm -rf /var/lib/apt/lists/*