Merge `Makefile`

[thoroc]

Clear and concise description of the problem

I have several project that uses Makefile and associated *.mk files. I'd like to make a permanent change so the config updater has those settings.

  "explorer.fileNesting.patterns": {
    "Makefile": "*.mk",
  }

Suggested solution

Add the following to the update.mjs file:

const base = {
  ...
  'Makefile': '*.mk',
  ...
}

Alternative

Re-adding the pattern matching on every config update.

Additional context

No response

Validations

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• [X] Read the Contributing Guide.
• [X] Check that there isn't already an issue that request the same feature to avoid creating a duplicate.