* fix(ui-cta): logic and UI for external and internal links
External links from the same domain (qiskit.org) should look like internal links and open in the same window. Other external links should open in a new window and show the respective icon.
* refactor(ui-cta): simpler check for URL protocol
* chore(ui-link): remove redundant `undefined` values
* refactor: avoid `else` after `return` statements
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Co-authored-by: Yaiza <yaiza.garcia.mm@gmail.com>