Fix link to profile in edited message

[TamaroWalter]

Note: Please fill out all relevant sections and remove irrelevant ones.

🔀 Purpose of this PR:

• Fixes a bug
• Updates for a new Moodle version
• Adds a new feature of functionality
• Improves or enhances existing features
• Refactoring: restructures code for better performance or maintainability
• Testing: add missing or improve existing tests
• Miscellaneous: code cleaning (without functional changes), documentation, configuration, ...

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📝 Description:

When a post is edited the link to the user profile did not appear correctly.

What was the problem?
The <a> element with the link was not created correctly

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📋 Checklist

Please confirm the following (check all that apply):

• I have phpunit and/or behat tests that cover my changes or additions.
• Code passes the code checker without errors and warnings.
• Code passes the moodle-ci/cd pipeline on all supported Moodle versions or the ones the plugin supports.
• Code does not have var_dump() or var_export or any other debugging statements (or commented out code) that
  should not appear on the productive branch.
• Code only uses language strings instead of hard-coded strings.

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🧾📸🌐 Additional Information (like screenshots, documentation, links, etc.)

This example shows how the link embedded before and after:

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