Move the `files` submodule over to `snippets`

[liamhuber]

It only depends on pathlib and seems generically useful to me, so off to snippets it goes!

[github-actions[bot]]

:point_left: Launch a binder notebook on branch _pyiron/pyiron_workflow/move_filesmodule

[codacy-production[bot]]

Coverage summary from Codacy

See diff coverage on Codacy

Coverage variation	Diff coverage
:white_check_mark: +0.00% (target: -1.00%)	:white_check_mark: 100.00%

Coverage variation details

| | Coverable lines | Covered lines | Coverage | | ------------- | ------------- | ------------- | ------------- | | Common ancestor commit (85f153d15a0a22f8427a6551ed3bcf716b1d6bc7) | 2572 | 2195 | 85.34% | | | Head commit (35b6d77ef7b1d04a97d22c213d6331d009b09438) | 2572 (+0) | 2195 (+0) | 85.34% (**+0.00%**) | **Coverage variation** is the difference between the coverage for the head and common ancestor commits of the pull request branch: ` - `

Diff coverage details

| | Coverable lines | Covered lines | Diff coverage | | ------------- | ------------- | ------------- | ------------- | | Pull request (#158) | 1 | 1 | **100.00%** | **Diff coverage** is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: `/ * 100%`

See your quality gate settings    Change summary preferences

_{You may notice some variations in coverage metrics with the latest Coverage engine update. For more details, visit the documentation}