Fix prevent redirection issue when clicking text or icon within button

[rsdeus]

🎩 What? Why?

This fix resolves the issue where clicking on the text or icon inside a button would fail to trigger the correct redirection, as event.target would capture the inner elements (<span> or <icon>) instead of the <a> element containing the data-dialog-open attribute.

📌 Related Issues

• Related to https://git.octree.ch/decidim/decidim-nightly/-/issues/18

Testing

• Given a Decidim proposal component configured to accept participant proposals
• As a non-registred user, I click on "New Proposal" text or "+" icon
  
• I complete my login/password credentials and login
• Error: I am back on the proposals component
• Expected: I go on the proposal creation, as I clicked to "New Proposal" button

♥️ Thank you!

[github-actions]

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