live reload does not works when the change is happened on entry of child compiler

[wood1986]

Bug report

I have a plugin which creates a child compiler and use a different entry for the compilation. It happens at parent's compilation.hooks.processAssets at Compilation.PROCESS_ASSETS_STAGE_SUMMARIZE stage . When I modify the child entry, it does not have a live reload but webpack did re-compile.

Actual Behavior

webpack did re-compile but webpack-dev-server does not have a live reload when the change is done in the child entry

Expected Behavior

webpack-dev-server should have reload when child compilation has change

How Do We Reproduce?

I have a fix ready. See my PR

Please paste the results of npx webpack-cli info here, and mention other relevant information