Minimal changes necessary for Webpack 5 compatibility

[Judahmeek]

Same as #400 without the lib directory.

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This change is 

[justin808]

questions below

Reviewed 6 of 6 files at r1, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @Judahmeek)

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src/utils/processStyleLoaders.js, line 66 at r1 (raw file):

    // eslint-disable-next-line no-param-reassign
    loadersWithSuffix[sassLoaderIndex] = sassLoaderWithSourceMap;

1. Will this break compat with older webpack?
2. Can you be sure to put in changelog?

[Judahmeek]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @justin808)

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src/utils/processStyleLoaders.js, line 66 at r1 (raw file):

Previously, justin808 (Justin Gordon) wrote…

1. Will this break compat with older webpack?
2. Can you be sure to put in changelog?

1. No, because sass-loader's latest versions already get their default sourceMap config from the devtools configuration.

2. Sure. How exactly do you want me to phrase it? bootstrap-loader no longer triggers sourceMap for sass-loader?

[justin808]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @Judahmeek)

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src/utils/processStyleLoaders.js, line 66 at r1 (raw file):

Previously, Judahmeek (Judah Meek) wrote…

1. No, because sass-loader's latest versions already get their default sourceMap config from the devtools configuration.

2. Sure. How exactly do you want me to phrase it? bootstrap-loader no longer triggers sourceMap for sass-loader?

Sure -- I really have zero idea on this one.

[justin808]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @Judahmeek)

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src/utils/processStyleLoaders.js, line 66 at r1 (raw file):

Previously, justin808 (Justin Gordon) wrote…

Sure -- I really have zero idea on this one.

maybe just a changelog entry!
maybe a major version bump also!

[justin808]

Please update the https://github.com/shakacode/bootstrap-loader/blob/master/CHANGELOG.md and I will merge and release.