Merge pull request #21694 from sebastian-philipp/dashboard-review-pylint

mgr/dashboard: Clean up Pylint warnings

Reviewed-by: Tatjana Dehler <tdehler@suse.com>
Reviewed-by: Volker Theile <vtheile@suse.com>

diff --cc src/pybind/mgr/dashboard/.pylintrc
Simple merge

diff --cc src/pybind/mgr/dashboard/controllers/__init__.py
Simple merge

diff --cc src/pybind/mgr/dashboard/controllers/rbd.py
Simple merge

diff --cc src/pybind/mgr/dashboard/tests/helper.py
Simple merge

diff --cc src/pybind/mgr/dashboard/tools.py
Simple merge