Update extensions.json

[Dintanthrir]

Add store page for Arrows(https://arrows.owlbear.rodeo.zalambar.com/manifest.json)

Make sure that your submission has the following:

• A link to the raw github markdown file with a YAML front matter definition containing:
  • The title of your extension
  • A description of your extension
  • The author
  • A hero image
  • An icon
  • Tags (these will help with your extension's discoverability)
  • A link to your extensions manifest

Please, go through these steps before you submit a PR.

• You have done your changes in a separate branch.

• You have a descriptive commit message with a short title (first line).

• You have only one commit (if not, squash them into one commit).

• Your pull request MUST target the main branch on this repository.

• Your pull request puts your extensions details as the last entry in the extensions.json file

[Several-Record7234]

Hi @Dintanthrir,

I've just run the first-level verification and no errors were thrown, so that's good, but I did note that your learn-more URL is very sparse - usually this link would include a minimal amount of user instruction for the extension. I don't think that this will be a showstopper for the publication of the extension, but it would be a kindness to your future users for you to add something helpful there! 😉

[Several-Record7234]

Validation script and image URLs check out fine. 'Learn-more' link works.

Extension functionality and API usage not checked.