revert: remove jest workers limit (using default)

package.json

@@ -23,7 +23,7 @@
     "start-breaking-cycle": "yarn pre-cycle && standard-version -t \"\" --prerelease rc --release-as major",
     "attach": "react-native attach",
     "postinstall": "patch-package && rn-nodeify --install path,buffer && chmod +x ./bin/add-ios-source-maps.sh && ./bin/add-ios-source-maps.sh && chmod +x ./bin/add-ios-env-config.sh && ./bin/add-ios-env-config.sh",
-    "test": "jest",
+    "test": "jest -w 1",
     "prettify": "prettier --write \"ts/**/*.ts*\"",
     "packager:clear": "rm -rf $TMPDIR/react-native-packager-cache-* && rm -rf $TMPDIR/metro-bundler-cache-*",
     "bundle:android": "node node_modules/react-native/local-cli/cli.js bundle --platform android --dev true --entry-file index.js --bundle-output ./bundles/index.android.bundle",