manager: tooling fixes & ci integration

The tooling of manager is broken due to changes in paths after integration with kresd's repository. This should mainly fix the linting step in CI and all other tools as well.

ci/images/manager/Dockerfile

+# SPDX-License-Identifier: GPL-3.0-or-later
+
+FROM fedora:35
+MAINTAINER Knot Resolver <knot-resolver@labs.nic.cz>
+
+WORKDIR /root
+CMD ["/bin/bash"]
+ENV PATH="/root/.local/bin:${PATH}"
+
+# Install Python
+RUN dnf install -y git diffutils python3.6 python3.7 python3.8 python3.9 python3.10 python3-gobject pkg-config cairo-devel gcc python3-devel gobject-introspection-devel cairo-gobject-devel which \
+	&& dnf clean all
+
+# Install Poetry
+RUN python3 -m pip install -U pip \
+	&& curl -sSL https://install.python-poetry.org | python3 - \
+	# not exactly required, but helpful
+	&& python3 -m pip install poethepoet