TinyMCE: Correcting wrong tip

[infograf768]

New issue.

As the new TinyMCE Sets are no more assigned depending on Access Levels but on User Groups, the tip was wrong.
To test, edit the Tiny Editor plugin

Before patch:

After patch:

@Fedik @ggppdk @AlexRed

Note: if someone has a better text to submit, I am open to proposals.

[Fedik]

I have tested this item ✅ successfully on 9ba0bd3

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[ghost]

I have tested this item ✅ successfully on 9ba0bd3

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[jeckodevelopment]

RTC

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