Update webext-sdk dependency to 0.4.0

Background / User story

We'd like to bring in the latest EWE features that benefit our users.

Milestone: %WebExt SDK 0.4.0 in eyeo/adblockplus/abc/webext-sdk

Dependency changes

• Name: webext-sdk
• New version: 0.4.0 (incl. 0.3.0)
• Breaking changes:
  • 0.4.0
    • eyeo/adblockplus/abc/webext-sdk#157 (closed) - Adding an existing filter again throws "storage_duplicate_filters" error.
    • eyeo/adblockplus/abc/webext-sdk#207 (closed) - Dependencies for building the SDK are no longer installed alongside other npm production dependencies.
• Other changes:
  • 0.3.0
    • eyeo/adblockplus/abc/webext-sdk#112 (closed) - Added support for customizing filter list recommendations.
    • eyeo/adblockplus/abc/webext-sdk#171 (closed) - Added support for exposing an experimental allowlisting API to websites.
    • eyeo/adblockplus/abc/webext-sdk#197 (closed) - Updated adblockpluscore to 0.7.0:
      • Added static filter list generation tooling for Manifest v3.
  • 0.4.0
    • eyeo/adblockplus/abc/webext-sdk#157 (closed)
      • Added support for attaching meta data to filters.
      • Added "filter_not_found" error when setting meta data of filter that doesn't exist.
    • eyeo/adblockplus/abc/webext-sdk#213 (closed) - Updated adblockpluscore to 0.7.1.

Integration changes

• Legal: N/A
• Development:
  • Stop using --only=production in npm run $ create.dist.ewe.
  • Handle new filter errors without a dedicated error message for now.

Hints for testers

• This change was merged into the feature-8 branch.
• Building the extension should succeed.
• Inserting multiple filters into the custom filter table's input field, when one or more of them already exist, should display an error message.