fix: add gh to custom (#56)

* fix: add gh to custom

* fix gh script multi arch

* Dockerfile use bash directly

* Update build-ubuntu.yml

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Co-authored-by: Ryan <me@hackerc.at>
Co-authored-by: ChristopherHX <christopher.homberger@web.de>

linux/ubuntu/Dockerfile

@@ -23,7 +23,7 @@ SHELL [ "/bin/bash", "--login", "-e", "-o", "pipefail", "-c" ]
 WORKDIR /tmp
 
 COPY ./linux/${DISTRO}/scripts /imagegeneration/installers
-RUN /imagegeneration/installers/${TYPE}.sh
+RUN bash /imagegeneration/installers/${TYPE}.sh
 
 ARG BUILD_DATE
 ARG BUILD_TAG=${TYPE}