fix(react-router): adding legacy peer dep flag during installation to support newer versions of npm until RR6 is released

Author: ShaneK

packages/react-router/test/base/scripts/sync.sh

@@ -15,4 +15,4 @@ npm pack ../../../../react
 npm pack ../../../
 
 # Install Dependencies
-npm install *.tgz --no-save
+npm install *.tgz --no-save --legacy-peer-deps