Option to add octicons SVGs in Contributors

[Andre601]

If doable, should there be a way to add and use GitHub's Octicons in the Contributor plugin's categories option.

To keep it simple could the syntax follow the basic :emoji: one, but perhaps with an octicons- prefix and a 12, 16 or 24 suffix to choose the size variant.

Example workflow:

- uses: lowlighter/metrics@latest
  with:
    plugin_contributors: yes
    plugin_contributors_sections: categories
    plugin_contributors_categories: |
      {
        ":octicons-book-16: Documentation": ["README.md", "docs/**"],
        ":octicons-code-16: Code": ["source/**", "src/**"],
        ":octicons-key-asterisk-16: Other": ["*"]
      }

The above example would now print an image, but instead of emojis would it use the book, code and key-asterisk SVGs from Octicons.

It would help keep a sort of consistent GitHub theme in your readme, as emojis (Especially raw ones) can clash with other sections of metrics.

[lowlighter]

Hi 👋 !

Yes it's pretty easy to implement since it's really similar to how GitHub custom emojis are supported.
It'll be done once #838 merge and should be available in later today on @master/@main branches.

I kept the :octicon-{name}-{size}: syntax because it's indeed what seems the more logical.
For convenience, if it's 16px the size prefix will be able to be dropped

Thanks a lot for your suggestion 👍