Update dependency webpacker to v5

[renovate]

This PR contains the following updates:

Package	Update	Change
webpacker	major	'~> 3.3' -> '~> 5.0'

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Configuration

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[renovate]

⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻️ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
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The artifact failure details are included below:

File name: Gemfile.lock

ruby 2.7.1p83 (2020-03-31 revision a0c7c23c9c) [x86_64-linux]
Successfully installed bundler-1.17.2
1 gem installed
The dependency tzinfo-data (>= 0) will be unused by any of the platforms Bundler is installing for. Bundler is installing for ruby but the dependency is only for x86-mingw32, x86-mswin32, x64-mingw32, java. To add those platforms to the bundle, run `bundle lock --add-platform x86-mingw32 x86-mswin32 x64-mingw32 java`.
Fetching gem metadata from https://rubygems.org/...........
Fetching gem metadata from https://rubygems.org/.
Resolving dependencies.....
Bundler could not find compatible versions for gem "activesupport":
  In Gemfile:
    rails (~> 5.1.4) was resolved to 5.1.5.rc1, which depends on
      activesupport (= 5.1.5.rc1)

    webpacker (~> 5.0) was resolved to 5.1.1, which depends on
      activesupport (>= 5.2)

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Edited/Blocked Notification

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