[backport v2.10.1] Embedding web-worker polyfill breaks sourcemap tools

[github-actions]

This is a backport issue for #12511, automatically created via GitHub Actions workflow initiated by @richard-cox

Original issue body:

Setup

• Rancher version: 2.9

Describe the bug
The BLOB code from web-worker is minified, and contains source maps that are then passed over by webpack - that creates a situation of minified code inside BLOB inside minified code which confuses some tools, eg.

jantimon/chrome-profile-sourcemap-resolver#4

That could be fixed, but the only reason to do so would be supporting very old (pre-2013) browsers, so we are better off removing the polyfill altogether.

Expected Result
Validation steps for QA

• Browser Tab 1 - Open Pods list and create a trivial pod
• Browser Tab 1 - Open browsers dev tools window --> Network tab --> WS tab --> socket connection for the cluster --> Messages tab
• EDIT: Browser Tab 1 - Refresh page
• Browser Tab 2 - Nav to edit page for pod and edit it
• Browser Tab 1 - See resoure.change message for pod just changed

Notes
Fallback brought in when fixing another issue - #6563

[richard-cox]

PR #12561

[IsaSih]

Tests pass in v2.10-a5c927cb670f3078d0bcbc55d59f84ed1db6a068-head