feat: add folder icon for internal folder

[aryaag]

Motivation and Context

• The folder name internal is a common pattern across multiple languages and frameworks
• Specifically, Golang uses the internal folder for internal packages [link]
• But there were no icons associated with it (nor any open pull requests about it)

Changes in this PR

• Add folder icon(s) for internal folder
• Add icons for both open and closed state
• Icon used is downloaded from materialdesignicons
• The color scheme is plain grey as it does not specific to any language or framework.
  • Color scheme is same as the folder-admin icon(s)

Screenshots (if appropriate):

• closed: https://imgur.com/UYwo8lv
• open: https://imgur.com/DCefXoO

[aryaag]

@PKief - any chance of getting this merged?

[github-actions]

Preview

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[github-actions]

Preview

Thank you for creating a pull request. This preview shows you how your icons will look on the different themes:

Check how your icons fit in a 16x16 grid with our Pixel Perfect Checker by following this link.

You can find more information on how to contribute in the contribution guidelines.

[aryaag]

@okineadev @PKief - Rebased the PR and addressed review comments. Please validate and merge.

[PKief]

I was wondering if you could make the icon align to the grid. Please read through the contribution guidelines to adjust it accordingly.

You can check the alignment by using our Pixel Perfect Checker.

Let us know if you have any questions regarding it.

[okineadev]

I was wondering if you could make the icon align to the grid. Please read through the contribution guidelines to adjust it accordingly.

You can check the alignment by using our Pixel Perfect Checker.

Let us know if you have any questions regarding it.

There are folder icons from the old version of material-icon-theme, we need to take the folder image from the new icons

[PKief]

To improve the quality and to reduce the maintenance effort regular refactoring of the project is inevitable. As much as we appreciate your work and contribution in this pull request, we realised that it was created a while ago and some merge conflicts occurred.

We have decided to close all PRs that no longer correspond to the current code base. This gives us the opportunity to provide a better overview of the remaining open PRs.

We would like to offer you to update your changes to the main branch and reopen the PR if the contribution is still relevant for you. Please contact us, we will be happy to help you resolve any conflicts.

Thank you for your attention and good collaboration.