Removed sharp from package.json (#12489)

### WHY are these changes introduced?

The reference to sharp package.json was causing issues in running local
builds. Removing the reference to resolve the issue.

### WHAT is this pull request doing?

Removed line  `    "sharp": "^0.31.2",` from package.json

### How to 🎩

🖥 [Local development
instructions](https://github.com/Shopify/polaris/blob/main/README.md#install-dependencies-and-build-workspaces)
🗒 [General tophatting
guidelines](https://github.com/Shopify/polaris/blob/main/documentation/Tophatting.md)
📄 [Changelog
guidelines](https://github.com/Shopify/polaris/blob/main/.github/CONTRIBUTING.md#changelog)

### 🎩 checklist

- [ ] Tested a
[snapshot](https://github.com/Shopify/polaris/blob/main/documentation/Releasing.md#-snapshot-releases)
- [ ] Tested on
[mobile](https://github.com/Shopify/polaris/blob/main/documentation/Tophatting.md#cross-browser-testing)
- [ ] Tested on [multiple
browsers](https://help.shopify.com/en/manual/shopify-admin/supported-browsers)
- [ ] Tested for
[accessibility](https://github.com/Shopify/polaris/blob/main/documentation/Accessibility%20testing.md)
- [ ] Updated the component's `README.md` with documentation changes
- [ ] [Tophatted
documentation](https://github.com/Shopify/polaris/blob/main/documentation/Tophatting%20documentation.md)
changes in the style guide

polaris.shopify.com/package.json

@@ -57,7 +57,6 @@
     "remark-gfm": "^3.0.1",
     "remark-slug": "^7.0.1",
     "remark-unwrap-images": "^3.0.1",
-    "sharp": "^0.31.2",
     "terminate": "^2.6.1",
     "use-dark-mode": "^2.3.1",
     "uuid": "^9.0.0",