[fix] fix duplicate outputs when using with multiple instances of HtmlWebpackPlugin

[toxic-johann]

I found a way to fix Duplicate outputs when using with multiple instances of HtmlWebpackPlugin.

It cause by two bug.

1. filesToInclude is shared by multiple compilation, which caused duplication.
2. It hasn't check if the chunk belong to the page, so it will inject all the chunk into every page.

solution

1. I move filesToInclude into each compilation. So they won't interfere with each other
2. I check the chunk by renderedHash, which is used by htmlWebpackPlugin.

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[toxic-johann]

I signed it!

[googlebot]

CLAs look good, thanks!

[toxic-johann]

hmmmm... Can someone review the pr ?

[9renpoto]

@toxic-johann Thanks! this PR works my project! 👍

@addyosmani Please review it.

[jeffposnick]

@addyosmani has asked me to lend a hand with this repo.

I don't see any red flags with this PR, and I trust based on the reactions and comments that it solves a problem that many folks were running into, so I'm fine with merging.

My one question for @toxic-johann is whether you'd consider this a major or minor change from a semver perspective (i.e. does it "break" existing functionality that others might have depended on). I'm trying to determine whether to tag this new code 2.1.0 or 3.0.0 on npm.

[toxic-johann]

@jeffposnick just a minor change

[jeffposnick]

Thanks for confirming, and thanks for everyone's patience.

[jeffposnick]

(I'll publish 2.1.0 to npm soon—I've asked @addyosmani to add me as an owner there.)

[jeffposnick]

2.1.0 is now live on npm, and tagged on GitHub: https://github.com/GoogleChromeLabs/preload-webpack-plugin/releases/tag/v2.1.0