Disables specific shellcheck errors to allow certain coding
patterns and removes an unused variable from the super-linter
workflow. This improves the linter's signal-to-noise ratio
and reduces unnecessary checks.
Relates to #4696
Configures the Super-Linter action to use `.shellcheckrc` as the
BASH_FILE_NAME. This ensures that shellcheck uses the correct
configuration file for bash script linting.
Fixes#4696