Implement rules and functions to format shell scripts:
$ make format.shell
or alternatively to format all source code:
$ make format
The formatter `shfmt` reads the rules from the editorconfig[1]
If any EditorConfig files are found, they will be used to apply formatting
options. If any parser or printer flags are given to the tool, no
EditorConfig files will be used.
[1] https://github.com/patrickvane/shfmt?tab=readme-ov-file#description
Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>