Fix empty %p in group creation step

What does this MR do?

Following discussion from #296507 (closed) and !48052 (comment 480218562), this MR aims at removing empty HTML element in the DOM and a flash alert.

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Before	After

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
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Availability and Testing

• [-] Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

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