Add Job Summary to check-valid-credentials

[zkamvar]

Since GitHub now has Markdown Job Summaries available, I can give a better alert for workflows that don't have valid tokens:

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⚠️ Missing Token

The SANDPAPER_WORKFLOW secret is missing, invalid, or does not have the right scope (repo, workflow) to update the package cache.

If you want to have automated pull request updates to your package cache, you will need to generate a new tokens, it will look something like this:

Steps to Generate a New Token

1. 🔑 Click here to generate a new token called Sandpaper Token (zkamvar/astromantic-atlanticspadefish) with the repo and workflow scopes from your GitHub Account
2. 📋 Copy your new token to your clipboard
3. Go To https://github.com/zkamvar/astromantic-atlanticspadefish/settings/secrets/actions/new
   • enter SANDPAPER_WORKFLOW for the 'Name'
   • 📥 paste your token for the 'Value'

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This will also allow me to remove a bulky reporting step from the update workflows