Support array entry point in webpack

Hi, my project have multi entry point. But, css-block throw error and requires only string

ERROR in Path must be a string. Received [ './utils/polyfill/index.js', './packages/profile/client.js' ]

Start by tracing webpack entry handling and the css-block code path that rejects the reported array of JavaScript entry files. Done means a multi-entry configuration using an array no longer raises the reported “Path must be a string” error.

Written by the indexing model from the issue text.