Update dependency @rollup/plugin-commonjs to v20

This MR contains the following updates:

Package	Type	Update	Change
@rollup/plugin-commonjs	devDependencies	major	^19.0.0 -> ^20.0.0

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Release Notes

rollup/plugins

v20.0.0

2021-07-30

Breaking Changes

• fix: Correctly infer module name for any separator (#​924)

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Configuration

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packages/app-shell/package.json

@@ -14,7 +14,7 @@
     "access": "public"
   },
   "devDependencies": {
-    "@rollup/plugin-commonjs": "^19.0.0",
+    "@rollup/plugin-commonjs": "^20.0.0",
     "@rollup/plugin-json": "^4.1.0",
     "@rollup/plugin-node-resolve": "^13.0.0",
     "babel-eslint": "^10.1.0",