我是新手，我在“ create-react-app my-app”时遇到以下错误：
Installing packages. This might take a couple of minutes.
Installing react, react-dom, and react-scripts...
yarn add v1.22.4
[1/4] Resolving packages...
[2/4] Fetching packages...
error An unexpected error occurred: "https://registry.yarnpkg.com/prop-types/-/prop-types-15.7.2.tgz: unable to get local issuer certificate".
Aborting installation.
Deleting generated file... package.json
Deleting generated file... yarn.lock
Done.
OS- fedora 30纱线版本：v1.22.4