chore(deps): update actions/checkout action to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v5 -> v6

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Warning

Some dependencies could not be looked up. Check the Dependency Dashboard for more information.

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Release Notes

actions/checkout (actions/checkout)

v6

Compare Source

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Configuration

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[liblaf]

✅⚠️MegaLinter analysis: Success with warnings

Descriptor	Linter	Files	Fixed	Errors	Warnings	Elapsed time
✅ COPYPASTE	jscpd	yes		no	no	1.54s
✅ JSON	prettier	8	0	0	0	0.36s
✅ JSON	v8r	8		0	0	4.49s
⚠️ PYTHON	ruff	yes	yes	2	no	0.29s
✅ REPOSITORY	git_diff	yes		no	no	0.01s
✅ SPELL	cspell	22		0	0	3.43s
✅ YAML	prettier	4	0	0	0	0.49s
✅ YAML	v8r	4		0	0	4.73s
✅ YAML	yamllint	4		0	0	0.4s

Detailed Issues

⚠️ PYTHON / ruff - 2 errors

N999 Invalid module name: '{{ package_dir }}'
--> template/src/{{ package_dir }}/__init__.py:1:1

N999 Invalid module name: '{{ package_dir }}'
--> template/src/{{ package_dir }}/__init__.pyi:1:1

Found 2 errors.

See detailed reports in MegaLinter artifacts