`SC1078` is a shellcheck error: https://www.shellcheck.net/wiki/SC1078. It does not originate in Geany.
You don't mention how or where you get this warning, so I'll assume it is by running some (possibly predefined) build action for a bash file. If you think the error is not incorrect or misleading, you'll have to speak to shellcheck maintainers instead. Their issue tracker is here: https://github.com/koalaman/shellcheck/issues