fix: !important in the prim-css editor is rendered incorrectly

[solidsniper]

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Description

Fixes #4994

Type of change

Please delete any options that are not relevant.

• User interface (UI)
  PrismJS text is not in sync with input text. Edited bold class to fix issue. PrismJS Reference: Wraped lines and textarea / pre PrismJS/live#15

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings
• My code needed automated testing. I have added them (this is optional task)

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[CommanderStorm]

Thanks for the fix! 🎉

Note

This PR is part of the v2.0 merge window => see #4500 for the bugs that need to be addressed before we can ship this release ^^

_{All changes in this PR are small and uncontroversial ⇒ merging with junior maintainer approval}