Update package.json (#66)

Running into a dependabot error in another repo when trying to update this package:
```
ReferenceError: repository is not defined
```

I think it has to do with how the `repository` value was defined here.

.changeset/ninety-berries-live.md

@@ -0,0 +1,5 @@
+---
+'@shopify/i18next-shopify': patch
+---
+
+Update repository field in package.config to resolve issues with DependaBot in consuming repositories.

package.json

@@ -15,10 +15,7 @@
   },
   "homepage": "https://github.com/Shopify/i18next-shopify",
   "bugs": "https://github.com/Shopify/i18next-shopify/issues",
-  "repository": {
-    "type": "git",
-    "url": "https://github.com/Shopify/i18next-shopify"
-  },
+  "repository": "https://github.com/Shopify/i18next-shopify",
   "devDependencies": {
     "@babel/cli": "^7.15.0",
     "@babel/core": "^7.15.0",