[bug] `make license-headers` should run on shell scripts

[ianlewis]

repo-template/Makefile

Lines 110 to 127 in 9747d1c

	git ls-files --deduplicate \
	'*.c' \
	'*.cpp' \
	'*.go' \
	'*.h' \
	'*.hpp' \
	'*.ts' \
	'*.js' \
	'*.lua' \
	'*.py' \
	'*.rb' \
	'*.rs' \
	'*.toml' \
	'*.yaml' \
	'*.yml' \
	'Makefile' \
	| while IFS='' read -r f; do [ -f "$${f}" ] && echo "$${f}" || true; done \
	); \

[ianlewis]

If I remember right, autogen.sh relies fully on the file extension to determine the file type. Many shell scripts don't have a .sh extension.