Bump webpacker from 3.2.1 to 3.4.1

[dependabot-preview]

Bumps webpacker from 3.2.1 to 3.4.1.

Changelog

Sourced from webpacker's changelog.

[3.4.1] - 2018-03-24

Fixed

• Yarn integrity check in development #1374

[3.4.0] - 2018-03-23

Please use 3.4.1 instead

Added

• Support for custom Rails environments #1359

This could break the compilation if you set NODE_ENV to custom environment. Now, NODE_ENV only understands production or development mode

[3.3.1] - 2018-03-12

Fixed

• Use webpack dev server 2.x until webpacker supports webpack 4.x #1338

[3.3.0] - 2018-03-03

Added

• Separate task for installing/updating binstubs
• CSS modules support #1248
• Pass relative_url_root to webpacker config #1236

Breaking changes

• Fixes #1281 by installing binstubs only as local executables. To upgrade:

bundle exec rails webpacker:binstubs

• set function is now removed from plugins and loaders, please use append or prepend

// config/webpack/environment.js
const { environment } = require('[**rails**](https://github.com/rails)/webpacker')

environment.loaders.append('json', {
  test: /\.json$/,
  use: 'json-loader'
})

Fixed

... (truncated)

Commits

• c57e970 3.4.1
• e93df6d Remove NODE_ENV declaration from rake task and production flag
• d418bcf 3.4.0
• eb1a637 makes header capitalization more consistent (#1368)
• 7c348fc Ignore /log directory from git (#1351)
• e616184 Detangle NODE_ENV and RAILS_ENV (#1359)
• 93386ed Remove webpack-dev-server upgrade (#1356)
• 811796a Add capybara configuration to testing.rb (#1340)
• 97e09e3 Update comment on check_yarn_integrity config (#1342)
• 0a7778a 3.3.1
• Additional commits viewable in compare view

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