Update SiteHeader.js

[linojon]

remove BLM banner

What: remove BLM banner

Why: the BLM concept may be good but the organization has been proven to be fraudulent and discredited ("buy large mansions")

How:

Checklist:

• Documentation
• Tests
• Code complete
• Changeset

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⚠️ No Changeset found

Latest commit: 402922d

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[Andarist]

Could you revert also all other changes that were introduced here: 214fb17 ? Unless keeping them still makes sense - I haven't rechecked this at the moment.

[srmagura]

no longer relevant