Update experimenta button documentation to reflect component name change

- Replace instances of <UiButtonButton> with <Button> in the documentation for the experimenta button.
- Ensure consistency in the examples provided for button, link, and NuxtLink usage.

docs/EXPERIMENTA_BUTTON.md

@@ -18,25 +18,25 @@ Der experimenta-Button ist eine spezielle Button-Variante, die das offizielle ex
 ### Als Button
 
 ```vue
-<UiButtonButton variant="experimenta" size="experimenta" @click="handleClick">
+<Button variant="experimenta" size="experimenta" @click="handleClick">
   Button Text
-</UiButtonButton>
+</Button>
 ```
 
 ### Als Link
 
 ```vue
-<UiButtonButton variant="experimenta" size="experimenta" as="a" href="https://www.experimenta.science/">
+<Button variant="experimenta" size="experimenta" as="a" href="https://www.experimenta.science/">
   Zur experimenta Startseite
-</UiButtonButton>
+</Button>
 ```
 
 ### Mit NuxtLink
 
 ```vue
-<UiButtonButton variant="experimenta" size="experimenta" as="NuxtLink" to="/some-page">
+<Button variant="experimenta" size="experimenta" as="NuxtLink" to="/some-page">
   Interne Seite
-</UiButtonButton>
+</Button>
 ```
 
 ## Props