fix(a11y): textarea aria describedby

[federico-ntr]

Same fix as 396c752

Fixes #

PR Checklist

• My branch is up-to-date with the Upstream main branch.
• The unit tests pass locally with my changes (if applicable).
• I have added tests that prove my fix is effective or that my feature works (if applicable).
• I have added necessary documentation (if appropriate).

Short description of what this resolves:

The change prevents adding a broken aria-describedby when no infoText is passed. In 396c752 the same change has been made, but textarea was not included for some reason, though it's affected by the same problem

Changes proposed in this Pull Request:

[vercel]

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[federico-ntr]

Noto lo stesso problema nel componente Upload, che però non mi risulta gestire nessun help text, quindi non capisco cosa ci faccia quel pezzo di codice. Mi sto perdendo qualcosa?