[docs] fix security warning in tutorial section Logic / Each blocks

[fredovecino]

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Tests

• Run the tests with npm test and lint the project with npm run lint

In the tutorial section "Logic / Each block" there is a warning in the editor:
Security: Anchor with "target=_blank" should have rel attribute containing the value "noreferrer" (13:6)

Affected page

REPL showing the fix

[baseballyama]

Thank you for catching this!
I added your commit to #8024.
(So your name will list to commit log.👍)

So I will merge #8024 and close this PR.