icon request: Upwork

### Describe the Icon

Please add a vector icon for Upwork, the popular freelancing platform. The icon should match the standard Upwork logo, ideally using a simplified and scalable design for consistency with other brand icons.

Requirements:
Flat design (monotone version)
Clean SVG path
A recognizable “Up” shape from the official logo
Suitable for UI/UX use (e.g., button, footer, dashboard)

### Links to Examples

https://en.wikipedia.org/wiki/Upwork#
https://www.upwork.com/about/brand/

### Additional Information

This icon would be helpful in applications or websites that integrate with freelance platforms or showcase social/professional links. It’s currently missing from most open-source icon libraries, so adding it would fill a gap for developers and designers alike.

No se identifica ningún archivo ni prueba en la issue. Empieza revisando el patrón existente de contribución de brand-icons del repositorio y las directrices de marca de Upwork enlazadas; se considera terminado cuando se añade un SVG de Upwork monocromo y reconocible, de forma coherente con el conjunto de iconos y adecuado para su uso en la UI.

Escrito por el modelo de indexación a partir del texto del issue.