Fix convertUnicodeToAscii text utility method

What does this MR do?

Following !39971 (merged), the new project page does not properly replace the character ö to oe and neither Ö to Oe. This MR fixes the responsible convertUnicodeToAscii method.

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Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
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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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• [-] The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
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