Can v1.6.2 add the runtime option？

[AttackXiaoJinJin]

Feature Proposal

my company has an old project use webpack4，and like #831 discussed，I also have a feature need the extraction provided by mini-css-extract-plugin (to get my .css files) and don't create link tag

Could you please add it? I'd also be happy to submit a PR for mini-css-extract-plugin v1.6.2 ！

Feature Use Case

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

"webpack": "4.44.2",
"mini-css-extract-plugin": "1.6.2",

[AttackXiaoJinJin]

🤔I thinked a while，we use style tag to add mini-css-extract-plugin extract css files when in SSR，BUT，in CSR，still need mini-css-extract-plugin add link tag，so close this issue