Don't compress development assets and fix deprecation warning in production

What does this MR do?

Removes CompressionPlugin from development config and runs it only in production. This should reduce webpack-dev-server's memory footprint and compile time.

Also replaces the deprecated NoErrorsPlugin with NoEmitOnErrorsPlugin (It's the same exact plugin, they just renamed it - see: https://github.com/webpack/webpack/pull/3570).

Are there points in the code the reviewer needs to double check?

yarn run webpack-prod should run, should produce *.gz files for all assets, and not have any deprecation warnings.

Why was this MR needed?

^

Screenshots (if relevant)

n/a

Does this MR meet the acceptance criteria?

• [ ] Changelog entry added
• [ ] Documentation created/updated
• [ ] API support added
• Tests
  • [ ] Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

n/a