🤖 Add file patterns to config.json

[ErikSchierboom]

⚠ This PR requires you to make a simple change before merging. ⚠

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To save maintainers from having to manually specify the files key in their exercises' .meta/config.json files, we are providing support for track-level patterns. See this PR for details.

This PR adds (purposefully wrong) file patterns to the config.json file. It is up to you, the track maintainers, to change these patterns to their correct value.

You can use the following placeholders:

• %{kebab_slug}: the kebab-case exercise slug (e.g. bit-manipulation)
• %{snake_slug}: the snake_case exercise slug (e.g. bit_manipulation)
• %{camel_slug}: the camelCase exercise slug (e.g. bitManipulation)
• %{pascal_slug}: the PascalCase exercise slug (e.g. BitManipulation)

We will soon update configlet to enable it to automatically populate the .meta/config.json file's files property, at which point we will then batch-PR updates to all tracks that have merged this PR.

Tracking

exercism/v3-launch#19