Ship pictogram updates in packages

[joshblack]

We currently ship pictograms that use a mix of stroke and fill attributes for styling, which can be confusing when it comes to styling. Instead, we're going to be receiving a batch of pictograms from brand where they are all going to be styled with fill. As a result, we will need to ship a breaking change for pictograms for these new assets. This work will include:

• Determining which pictogram assets should be marked as deprecated and ship them in a minor release - issue: Determine changes in pictogram assets #6923
• Create a migration guide that helps teams know which assets to update to in the latest version
• Bring over the newest pictogram assets after shipping the minor release
• Reset the deprecated.yml file and remove any pictograms we no longer want to ship
• Ship a new version of our Sketch plugin that includes pictograms based on these changes to fill