🤖 chore: Add cover key in .babel.env.

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  - https://github.com/make-github-pseudonymous-again/rejuvenate/blob/9b50c2a1d7e9ab7b4bc9c9ff88892e98c5f62244/src/transforms/package.json:ensure-babel-env-cover.js
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Author: a-flying-potato

package.json

@@ -126,6 +126,7 @@
           ]
         ]
       },
+      "cover": {},
       "development": {
         "sourceMaps": "inline",
         "presets": [