shared/install: modernize and eliminate the use of basename() #22570

	---
	# https://github.com/redhat-plumbers-in-action/differential-shellcheck#readme

	name: Differential ShellCheck
	on:
	push:
	branches:
	- main
	pull_request:
	branches:
	- main

	permissions:
	contents: read

	jobs:
	lint:
	if: github.event.repository.name != 'systemd-security'
	runs-on: ubuntu-latest

	permissions:
	security-events: write

	steps:
	- name: Repository checkout
	uses: actions/checkout@9bb56186c3b09b4f86b1c65136769dd318469633
	with:
	fetch-depth: 0

	- name: Differential ShellCheck
	uses: redhat-plumbers-in-action/differential-shellcheck@c15070885a82a2c93db8a765d332c38c50dde8b3
	with:
	# exclude all `.in` files because they may contain unsupported syntax, and they have to be preprocessed first
	# TEMPORARY: exclude bash completion files, they would generate too many defects in Code scanning dashboard (600+)
	# exclude zsh completion files, zsh is not supported by ShellCheck
	exclude-path: \|
	'*/.in'
	'shell-completion/bash/*'
	'shell-completion/zsh/*'
	token: ${{ secrets.GITHUB_TOKEN }}

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