chore(deps-dev): bump @react-native-community/cli in /packages/rn-tester

Bumps [@react-native-community/cli](https://github.com/react-native-community/cli/tree/HEAD/packages/cli) from 15.0.0-alpha.2 to 20.0.0.
- [Release notes](https://github.com/react-native-community/cli/releases)
- [Changelog](https://github.com/react-native-community/cli/blob/main/packages/cli/CHANGELOG.md)
- [Commits](https://github.com/react-native-community/cli/commits/v20.0.0/packages/cli)

---
updated-dependencies:
- dependency-name: "@react-native-community/cli"
  dependency-version: 20.0.0
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

packages/rn-tester/package.json

@@ -50,7 +50,7 @@
     }
   },
   "devDependencies": {
-    "@react-native-community/cli": "15.0.0-alpha.2",
+    "@react-native-community/cli": "20.0.0",
     "@react-native-community/cli-platform-android": "15.0.0-alpha.2",
     "@react-native-community/cli-platform-ios": "15.0.0-alpha.2",
     "commander": "^12.0.0",