Performance issue

[PeterDaveHello]

If there are too many libraries been touched in a single PR, list all of their package.json in .git/info/sparsecheck will make sparseCheckout super slow, even slower than put a simple rule /ajax/libs/*/package.json in it, then we'll get timeout on CI.

Need to take some time to find the threshold of how many single library package.json checkout rules will spend more time than using /ajax/libs/*/package.json to checkout all the package.json, then directly use /ajax/libs/*/package.json if there are more than x libs been touched in a PR.